1996 Four Winns Sundowner with 5.0 Cobra engine and drive

Lpgc

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The boat is still on the river around 30 miles from home, had two sessions on it today. Went around midday with the missus, did around 10 miles North on the river, turned around and back the 10 miles to the mooring. When we first got to the boat the trim worked and continued to work for around 10 minutes after starting the engine. When I went around 6pm with my son I hoped the trim would work again (maybe after the engine bay had cooled down) but it didn't. I'm still wondering if the trim problems could be heat related, is there a thermal cutout? I thought the red protrusion on the side of the trim solenoid (I think that's what it is attached to the pump assembly?) looked like a circuit breaker but when I went with my son I tried to press it and it didn't move. I suppose the engine bay would still be warm after the drive up river with the missus when I went with my son because it would only have had 2 hours to cool down. If the trim works next time I use the boat (when the engine bay is still cool) I'll be suspecting the problem is heat related even more.

Took a multimeter when I went with the missus but didn't use it when the trim seemed to work. It was getting late when I went with my son so still didn't use it. The only things I did to try to diagnose it were to try moving the trim power connection plug and try pressing the 'red button', neither of those things made any difference. I did check the ignition timing when I went with missus, seems set at 11BTDC which is very close to what I would have aimed for (its supposed to be 10BTDC but I'm running 97octane) so I left it as is.

There are quite a few wires enter the solenoid pack on the side of the pump but I think I'll be able to work out what wire does what, I expect the solenoid pack acts like the relays you mentioned and serves to send power to the pump motor with one polarity when the up button is pressed and opposite polarity when the down button is pressed... If that is true then if there is a problem with the solenoid pack I could replace it or even make a solenoid pack from relays.

I think you're on to something with debris in the thermostat. Today I ran the boat on the plane for a longer time than I did yesterday and the gauge stayed around 150 on the plane but went down to 125 at around 6knots. I have noticed the gauge go up slightly soon after slowing down after being on the plane but I kind of expected that. Not getting hot enough isn't good for the engine but it's much better than getting too hot. I'll have another look at the thermostat, I didn't put any sealant on the gasket so it should be easy to unbolt it and put it back together. Haven't seen any fluid leaks from the engine yet and the bilge is staying clean.
 

Lou C

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I think you're going to have to find a wiring diagram for your trim system because it's different than mine. If you can't find an OMC Cobra one, remember the Volvo SX of same year should be the same.
A couple of odd things that have happened over the years, and solutions....
when I first had the boat, when I'd hit the trim button, the engine would stumble, not every time but often. Accompanied by the voltmeter gauge twitching. Turned out to be lousy automotive grade battery cables. The amp draw of the trim system was enough to lower the system voltage low enough to stumble the ignition system. Dumped the junk cables, replaced with Ancor marine cable, and a dual battery system. No problems since.
Next, when I got rid of the cheap looking plastic wheel for a nice stainless destroyer style wheel with a roller knob (handy for docking) sometimes if I were touching the wheel while using the trim, I'd get a slight tingle. Turned out to be a bare spot in the trim wiring inside the remote control. Fixed that one with liquid electrical tape.
You probably won't believe this but, every now and then I have had the low temp reading because of something stuck in the stat. So I got to thinking, maybe a little vibration on the stat housing, will jar that loose, so I don't have to take the whole dang thing apart on the mooring, etc. Ran up on plane, got it good and hot, and brought it back to idle. Took the 3/8ths ratchet out of my on board tool kit and just tapped all around the stat housing. To my surprise, it worked! I've done this twice over the years. Sounds quite silly but it worked.

Just remembered one more oddball thing that happened this was with the trim also. One day just stopped working, I forget if it was up or down. Noticed that the relay had some corrosion on it, apparently water would leak thru the cover, behind sun pad and right on the relay. What I did was relocate the relay, cleaned up all the terminals, and after re-connecting the wires, coated with Evinrude triple guard grease, no more trim problems, till that one cylinder sprung a leak, last summer. That, is the last thing I fixed, works perfect, what a deal, $55 in parts to rebuild each cyl, you don't even have to remove them from the boat, as long as you can get the end cap off. That saves you from having to deal with those hydraulic line fittings.
 
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Lpgc

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Some good news and bad news today.... I visited the boat again with intention of just spending an hour looking at the trim tilt/system, I've only just got back from that but had more time on the boat than I expected. I was expecting a customer collecting their newly LPG converted vehicle from me late afternoon but while I was there they txted me to say they wouldn't get here until 8pm (later than expected). I quickly fixed the tilt/trim system, the problem turned out to be a very easy fix, just a case of a bit of corrosion in the connector plug that supplies the tilt/trim system with electrical power. I just unplugged and plugged it back in a few times and the tilt trim has worked fine since. Then, knowing I had extra time I decided to go for a quick run up the river in the boat by myself and gave it a little more stick this time, still not flat out but I had Google maps showing GPS speed on my phone and had it up to 36mph going upstream while I tested the trim could work against the engine load.

Then turned around again and driving slowly past some moored boats half a mile from the mooring spot the engine just died! No nasty noises or anything. So I turned the key to start it and it sputtered as though trying to start, so I gave it a couple of dips of the throttle and it started and ran for a couple of seconds before dying again, so I strongly suspect and hope that it is a simple case of me running it out of fuel. I was surprised when I got to the boat today because I thought when I left it last night the fuel gauge was reading 1/4 full but today it hasn't shifted from pointing to empty. I've been putting nearly 5 gallons in it from a jerry can before every trip and I know it will be using a bit more than that but the tank was already between a quarter and a half full before I first used it on Sunday (and added the first nearly 5 gallons from a jerry can). Still I think it's probably used more fuel than I thought. A bit of a sinking feeling (not literally sinking) when you break down on the water, especially on a midweek evening with few other boaters around. Phoned the guy who works at the marina and lives on a boat near the mooring, pleased that he picked the call up, I said "Its me who left your mooring 45 minutes ago, bit embarassing but I think I've run out of fuel". He laughed and said he'd have a ride up on his little inflatable, I asked "Are you bringing some fuel", he said "No I'll tow you back" and he did. Very good of him I thought, I asked how much he'd want to come out to me and he said "Nothing you're alright". When we'd finished I wanted to give him at least a few quid to buy a few pints but he'd already disappeared into his house boat with his young daughter so I thought I'll see him next time I visit the boat and give it him then.

Oops 😂

I'm sure there's nothing wrong with the engine, worst it could be really is something like the mechanical fuel pump, blocked fuel filter, blocked pick up pipe, water in fuel (doubt it because I got rid of the water that was in the tank), or most likely my fault for running the tank empty lol.
 

Lpgc

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@Lou C You probably already read my post above, I remembered what you said about tapping the thermostat housing today, set off on the river and the gauge didn't move from 120F so I was in 2 minds whether to give it much throttle, then I thought giving it some throttle would probably increase the temp a bit anyway so that's what I did. But I did think about tapping the stat housing, just a bit worried in case the cast shattered because the lower stat housing already has a chunk missing out of one of the bolt holes.

I've mentioned when I owned/rebuilt a 1982 Mercury 70hp engine on forum before, what I didn't say about that was I'd sometimes get a shock from the throttle lever and/or ignition key. Years ago when I had a small speedboat with that engine on it (and the shock problem) I took my son and his friend boating for a couple of days at 'Shell Island' in Wales. We launched the boat from the slip into the estuary (meaning they climbed into the boat from the front while I had to get wet pushing the boat out).... Then I decided to reach into the boat to turn the key and make sure the engine started before I climbed aboard myself. I had already set quite a wide throttle opening on the controls to help the engine start, then I turned the key while up to my chest in the water and got a series of electric shocks while turning the key lol. Then it started and I got more shocks but the engine started revving really high and I was worried it was gonna overrev.... So I had the choice of either letting the engine overrev and break it or get more shocks and turn the key off. I turned the key off. My son and his friend thought it was all very funny. Then we went out on the boat (we probably shouldn't have) and I had to put a plastic bag over the throttle to insulate myself from getting electric shocks.

Heh, on the first day of that trip my sons friend was so tired (probably been up all the night before playing computer games) that he fell asleep whilst sat in the back of the little 14 foot boat beside the very noisy 2 stroke motor with it's cover removed while I drove it hard and fast on the sea bouncing on the waves.
 
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Lou C

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I bet there was a bare spot in one of the trim wires inside the remote control.
About the possible fuel issue I’d add a bit more fuel & try again. In your you tube vid it looked to be running great.
 

Lpgc

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I bet there was a bare spot in one of the trim wires inside the remote control.
About the possible fuel issue I’d add a bit more fuel & try again. In your you tube vid it looked to be running great.
Thinking about it now, yes I bet there was a problem in the remote control.

It ran great again today.

Yes I was thinking I'll just take another 5 gallons in a can, pour it in and see if it will run. But now I'm wondering if I should lift the floor above the tank, remove the level sender and eyeball the fuel level in the tank / maybe disconnect the fuel line from the filter and try sucking on it / unscrew the filter water separator and see if contains any fuel (or water). I'm confident it will just be an empty fuel tank though... I'd got it in my head that when I fitted the new level sender and fixed the dash fuel gauge I'd set it up so an empty reading was really a 1/4 tank reading, but now I remember I set it up so empty means empty lol, it will show empty with the tank up to 1/4 full but with a full tank the gauge goes past the full mark. I drained the tank to somewhere around 1/4 full in the yard before Sunday (Sunday was when I launched) to drain water out and to make sure when I topped up with fuel the average octane would be good, added 5 gallons from a can before the launch on Sunday, added 5 gallons Monday dinner time and added another 5 gallongs Monday tea time... I knew I'd be using more than I was adding but I knew there was the 1/4 tank buffer, I now think it will have used all 15 gallons I put in from cans and all the 1/4 original tank contents so probably is empty.

I meant to ask the guy from the marina who gave me the tow what hours the fuel pontoon is open but he'd already gone back to his boat before I got the chance. Probably just a 9>5 service.

Not the best part of today hehe
20240611_182646.jpg

Forgot to mention I tried a gizmo today, an LCD diplay thats shows RPM and has it's own temperature sensor, can be programmed to alarm above a programmed RPM or temperature. Great for showing digitally accurate rpm (for setting idle speed etc), I plan on fitting it on the dashboard (will need to extend the wiring) and fit the temp sensor to the section of exhaust that contains the bellows on one side of the engine. Might even buy a second one and fit its temp sensor to the opposite side exhaust. Seems to me that during engine warm-up from a cold start if the raw water pump doesn't work properly the first thing to be damaged would be rubber parts of the exhaust before the engine overheated?

20240611_165526.jpg

Temp sensor, comes with adhesive strips to attach to anything.
20240611_165547.jpg

I just temporarily set it up on the engine to check accuracy of the instrument cluster tacho, which as expected shows double actual rpm. Yellow wire to coil negative. The gizmo uses its own watch battery.

20240611_165730.jpg
 
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Lou C

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Every spring when I get the boat ready I dump out the contents of the fuel filter into a mason jar to check for water and debris. And every year it looks fine so I just dump it in the lawnmower gas can and install a new fuel filter.
 

Lou C

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I like the idea of being able to monitor exhaust temps. Volvo actually had this as an option and with a sending unit on each exhaust elbow to feed back data. I do it the old fashioned way; I keep an IR temp gun & check them every so often. I usually get 90-100* at idle and the hottest they may get is 135-140 after coming off plane. Then they will cool down pretty quick. It’s worth checking because on inboards the exhaust can overheat while the temp gauge still reads normal. And yes to answer your question the rubber exhaust boots are the first to suffer. Often elevated temps on the exhaust system is a sign that they have corroded internally to the point where the cooling passages get clogged and the exhaust will get really hot because cooling water can’t pass through. In salt water by about year 7.
 
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Lpgc

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Didn't go to the boat yesterday, just got back from a short visit, put nearly 5 gallons in from a jerry can and it started 2nd attempt so it seems it was just out of fuel like I expected.

Then me and my mate took it the short distance to the fuel pontoon and put some more fuel in, carried on up river a bit to an area with no boats moored on the banks and gave it a bit of stick, no problems
:-)
 

Lou C

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Sounds good, boat fuel gauges aren't that accurate as it is. I always fill mine up when I get to 1/4 tank. I have 2 fuel docks nearby so it's not an inconvenience unless people are sitting at the dock there doing things that they aren't supposed to do like washing their boat!
 

Lpgc

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Sounds good, boat fuel gauges aren't that accurate as it is. I always fill mine up when I get to 1/4 tank. I have 2 fuel docks nearby so it's not an inconvenience unless people are sitting at the dock there doing things that they aren't supposed to do like washing their boat!
As you know, all the gauges on my dash including the fuel gauge didn't work when I first got the boat last year, then this year after rebuilding the engine I fixed all the gauges and fitted a new straight up/down reed switch type fuel level sender. Before fitting this sender I wired it in and set the gauge so it showed empty with the float at the bottom. The gauge goes beyond the full mark when the float is at the very top.

I think the problem is that I will have been readin the gauge wrong on the water. When the boat was on the trailer the gauge did show 1/4 tank when the tank was around 1/4 full but on the water the stern sits lower than the bow and the sender is fitted near the rear of the tank.

I wish I'd checked the gauge again today before I put the first 5 gallons in the tank, I didn't because that would've meant climbing into the boat to turn the ignition on then having to climb back out to add the fuel. But I dare say the guage would still have showed empty before I added it. The thing is, when I'd added just 5 gallons the gauge showed half and it's a 25 UK gallon (29 US gallon) tank so 5 gallons from empty shouldn't even show 1/4 full. Fuel is more expensive from the marina/fuel pontoon (and its expensive enough even from forecourts in the UK) so I prefer to buy from forecourts and pour it into the tank. I only added another 6 gallons at the marina / fuel pontoon, so at this point it would have had around 11 gallons in the tank (still less than half full) and the gauge fluctuated between reading 1/2 and 3/4 full.

In future I'll need to remember that the gauge might read between 1/2 and 3/4 full when there's only 11 gallons in the tank, and that when full the gauge will read past the full mark. Or I could move the pointer on the fuel gauge so when it would currently read 1/4 now it would read empty instead (and empty would be pointing at less than empty on the gauge), but I think it'll be OK if I remember how the gauge works now without having to move the pointer on the gauge.

Last couple of times I used the boat (today and the evening of the day before yesterday) the temp gauge didn't move from the 120F position until I gave it some stick and even then only got up to 150F. I'm pretty sure the gauge is accurate, put my hand on the inlet manifold and on the pipe between circulation wp and thermostat housing they both felt cool. After giving it some stick today the gauge settled at 140F. I'll need to remove the top half of the thermostat housing and check for debris in the stat like you said.

What temp should the gauge read? How soon should it get there at say 1000 rpm plodding up the river past moored boats? I know it'll read higher for a short time after slowing down from planing speed but what should it read on the plane? (and not that I've tried it yet what should it read flat out?).... Is 150F or 170F better? 150F is the pointing straight up position on my gauge.
 
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Lou C

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Mine has always run pretty close to the opening temp of the thermostat, 160*. On plane it will be at 160 it maybe a little less. It will rise a bit higher after coming off plane (170-175) but after either idling or slow speed running like at no wake speed it comes right back down to 160.
My 1988 Horizon 200 has a 44 gallon alu tank. That makes it easy figuring how many gallons is in the tank at any one time because 1/4 = 11 gal, 1/2 = 22 gal, 3/4 = 33 gal. Once you have been using it for a while you’ll have an idea how many gallons per hr you use & makes it easier to anticipate when you have to fill up. In my use the 4.3 V6 with the 4 bbl Quadrajet is quite economical, usually I average about 4.5 gal per hr as long as my cruise speed (3500 rpm, about 22 mph) doesn’t get the secondaries to open. The Quadrajet has small primaries and huge secondaries; so it can be pretty economical but still has the power when you need it.IMG_7629.jpeg
 

Lpgc

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Pulled the boat out of the little river today but before I did we went for another short ride on it. And before that I removed the thermostat top housing to see if there was any debris seeming to hold the stat open. there was but I didn't have the right tools to remove the debris so just refitted the housing. Again the engine ran too cool until I gave it some stick. For the first time today I opened it up and got the dash speedo reading 45mph with the weather cover up but forgot to check speed with GPS. Still pleased with the performance though :)

This was an earlier run on the plane not opened up, probably around 35mph.

I worry about running the engine too cold but hehe giving it some stick the temp comes up to close to what it should be. I will be taking the stat housing off again first opportunity now it's back in the yard. Will also look at changing the setting (number of engine cylinders?) on the back of the dashboard instrument cluster to try to get the revcounter reading properly instead of reading double.

No more problems with the tilt/trim :)

I'll be doing an oil change now it's had a few hours running after the engine rebuild.

I didn't get wet at all getting the boat out, drove it onto the trailer then climbed out the front and walked down the trailer to dry land. Step son got wet by wading in to connect the winch lol. I need to develop a system for getting it on/off the water quicker though (strapping it down, fitting trailer lights etc), it's currently taking too long but it is only the 2nd time I've launched/retrieved it. Got it near perfect driving it on but seemed an inch more to port on the carpeted planks (I forget the better term) than to starboard so dipped it in the river again and slightly repositioned it.

Don't like the arrangement at the front of the trailer with the 2 x high bow rollers. How the trailer is set up now the winch shackle and bow U bolt have to roll over the lower roller and it seems a bit messy, already chewing up that bottom roller. I see the point of having 2 x high bow rollers on the trailer but they're not set at a good height, if the lower roller (or both) were a bit lower it would avoid the shackle and boat U bolt hitting the lower roller.
 
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Lou C

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Post up a pic of the boat on the trailer
It took me several seasons to get the trailer the way I wanted it to be….trailer was too short so I fitted a longer tongue & longer roller bars and added more rollers. Then lowered it on the trailer by fitting lower crossmember brackets. Added a bow roller up front and adjusted the bow winch so the strap is straight. Last upgrade was installing a custom 2x3 6,000 lb axle with 12” surge brakes & 15” tires. With this set up I can easily launch & load the boat myself although the boat sits on a mooring behind my house all season….
 

Lpgc

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Post up a pic of the boat on the trailer
It took me several seasons to get the trailer the way I wanted it to be….trailer was too short so I fitted a longer tongue & longer roller bars and added more rollers. Then lowered it on the trailer by fitting lower crossmember brackets. Added a bow roller up front and adjusted the bow winch so the strap is straight. Last upgrade was installing a custom 2x3 6,000 lb axle with 12” surge brakes & 15” tires. With this set up I can easily launch & load the boat myself although the boat sits on a mooring behind my house all season….
I meant to take pics of the boat on the trailer today but didn't get around to it, I'll do that over the next few days but will be tied up with work Monday and Tuesday.

It's a bunk trailer with just a few rollers, the front roller is a doubled up (2 rollers) design that pivots so both rollers contact the front of the hull. I think the trailer is big enough for the boat but probably not set up right.
 

Lpgc

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Trailer pics

Don't like the way the bow U bolt has to ride over the lower roller
20240621_182504.jpg

Front keel roller doesn't even contact the boat
20240621_182518.jpg

There are no other rollers, the boat just sits on the bunks

20240621_182557.jpg 20240621_182606.jpg


The VHF seems to work, haven't tried talking to anyone on it yet but it powers up and I can listen to static lol. The combined on/off/volume knob is broke but I found out I can turn it on pressing the middle of the broken knob. It has GPS capability but does it need a separate aerial for the GPS to work (I should've looked at the sockets on the back before refitting it on the boat)?

20240619_182123.jpg

It's done a few hours on the river now after the engine rebuild so I canged the oil. Pumped the old oil out via the dipstick tube, changed the filter, refilled with oil then decided to start the engine for a few seconds to make sure the oil pressure was good and recheck oil level after it had filler the filter. Had a problem at this point, didn't realise the seal from the oil filter had stuck to the engine so when I installed the new filter there were 2 filter oil seals fitted.... Oil pressure stayed at 0psi for a second then went up to only 20psi then dropped to 0psi again. I turned the engine off and found oil had pumped into the bilge :-( . Realised the mistake and fixed it, now oil pressure is 40psi straight after starting. Tilted the boat as bow high as I could and removed the drain plug to get most of the oil out but I'll be cleaning the bilge. What's the best way? I was thinking of squirting some washing up liquid in the bilge, getting the hosepipe in and scrubbing / mopping. Heh I jet washed the bilge clean before fitting the engine, now it's dirty again and will soon look even worse unless I get the oil out.

I have some oxalic acid powder to clean the boat and get some rust marks off but haven't tried using it yet. Does oxalic acid damage trim stickers on the hull?
 

Lou C

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About the trailer
For the bow stop you want the bow eye just under the upper roller, the way it is the bottom roller looks likely to catch on it & make it hard to get the boat on & off. That lower roller is adjustable and you can just raise it slightly. You main bunks look ok from what I can see. The VHF, well here in the US we have dedicated channels for emergency (Ch 16) and other non emergency communications (Ch 9). So what I do every so often is call for a radio check on Ch 9, I usually get back “loud & clear”. This way you know you can transmit. I have 2 VHFs; a hard mount & a portable. On one I monitor Ch 16 on the other I monitor Ch 9. Both have GPS and the panic function where if you have an emergency you can transmit to the Coast Guard & this also transmits your location to them. Might not be necessary in many locations but is nice in larger bodies of water.
 

Lou C

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I had the same problem with the bow stop because I had lowered the boat on the trailer by about 2-3”. So I would up lowering the winch stand to get the strap level and flipped the bow stop to get it to fit right. Much better now when I launched it this season it just rolled off like it should.
 

Lpgc

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Thanks for the tips about the trailer, I'll keep in mind what you said and see if I can adjust it.

Does the radio need something else plugged in (like a GPS aerial) for the GPS to work?

I used to be familiar with use of marine VHF because dad had boats when I was growing up. My friend has a boat and he used to work for Ofcom which is the UK's office of communications that regulates radio use, he's giving me some reminders on how to use it. I didn't know if my VHF was UK spec or American spec or if there was any difference with frequencies etc, he told me we use the same channel numbers for the same things and most channels use the same frequencies but a few of the ship to ship channels are on different frequencies. As it turns out it doesn't matter because this radio can be set to US, Canadian or international (rest of world) mode.

Before cell phones dad used to occasionally make phone calls on VHF, he had a VHF on his boat and another in his RV, once made a call from the RV parked top of cliffs at the coast not far from where his boat was in the harbour. After the phone call Anglesy Radio (like a radio centre for the coastguard) radioed us saying we were giving a very strong signal for the distance they'd triangulated our position to and wondering why their triangulation pointed to us being slightly inland (we're not supposed to use marine VHF inland on vehicles etc). Dad told them maybe their triangulation was off by a few hundred yards because we were in the harbour... But we're sure they knew lol.
 
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