1996 Four Winns Sundowner with 5.0 Cobra engine and drive

Lou C

Supreme Mariner
Joined
Nov 10, 2002
Messages
12,671
That year VW would be a 1967, here in the US it also got a 1500 cc engine with 53 hp, prob my favorite Beetle because it has the classic old style but with more hp & 12v system. One day I’m going to get one. Looking for a Time Machine!
As far as DC electrics even the USA habit of calling the neg side a ground is not really correct, that applies to AC electrics more correctly. In AC the ground is a safety feature (green wire in USA).
 

Lpgc

Petty Officer 1st Class
Joined
Jun 17, 2023
Messages
258
Been on the boat on the little river again today, just by myself. Asked my missus, son, daughter, sister, friends, and a customer (whose car I still had in the yard) if they'd like to come for a ride on the boat but they were all either busy or didn't want to, I wanted to so went myself and had the radio for company.

Incidentally, pic of same customer's car I've done a bit of work on recently. He likes American cars and has quite a collection, mostly Hemi powered stuff but also some Ford stuff like this early 2000's Mustang. Loads of custom bits on the Mustang including engine bits such as cam, intake manifold. exhaust, shifter. etc. But he says the Mustang looks like a fast car, some of his other stuff is fast including his 1000bhp Jeep that I converted to LPG.

20240905_181735.jpg

20240905_181336.jpg

Back on the subject of the boat...

The relay I fitted (triggered by the purple wire from ignition, connects thick red wire battery power to the purple wire engine side of the relay) seems to have been a good idea, the coil is getting full battery voltage and there are no clicking noises from the VHF now, though I can still hear some alternator whine at low rpm sometimes.

The old thermostat I refitted seems to hold temp at 130/140F at and just above idle, around 150 at 30mph and 3000rpmm but still sometimes climbs past 170F at higher loads.

Dash temp reading fluctuates on the plane a little, say between 140 and 160 at 3000rpm but it seems it would run for hours like that with no problems

Flat out between 44 and 47 mph the temp reading sometimes climbs to 190+ and I've thought I could smell burning. Also flat out for more than say 1 minute the engine seems to start losing power. The temp reading, burning smell and drop in power prompted me to throttle back. A couple of times after giving it full throttle I stopped completely and could really smell burning, had a look at the engine and the lower end of the risers was too hot to touch but the higher end of the riser was normal temp.

Not sure what could be causing these symptoms, doubt it will be the thermostat, but over winter I'll rebuilt the raw water pump, rebuild the carb (already have the kit), maybe fit a new mechanical fuel pump, maybe fit a new thermostat housing, maybe pull the drive in case the seal on the water intake channel is compromised and causing it to be picking up some air.

Would appreciate any ideas regards the temp / burning smell issues.

Overall a good day on the river, but if the boat is supposed to be able to handle full throttle for extended periods I want it to be able to do that so want it fixed.

Thought occurred to install a GPS mph gauge on my phone on the ride back down the river today, seems the boat speedo is more accurate than I would've thought. Before I installed the app I had the boat speedo up to 47mph, after I installed the app I had the boat speedo up to 44mph and the GPS app agreed speed was 44mph. Speedo seems to over-read by 2mph at around 35mph.

Left the boat on a mooring on the river so will be visiting it at least once again over the next few days/week before bringing it home.
 
Last edited:

Lou C

Supreme Mariner
Joined
Nov 10, 2002
Messages
12,671
Love the Mustang. That’s a modern interpretation of the 1969-1970 Boss 302 that was sold to make it legal for Trans Am racing.
I agree you should be about to run WOT without overheating
 

Lou C

Supreme Mariner
Joined
Nov 10, 2002
Messages
12,671
Temp & burning smell
Check your manifold, elbow & rubber exhaust hose temps at idle and after running on plane.
I have basically the same style exhaust but with a different impeller design.
Idle : 90-100* F barely warm
After coming off plane: 135-140…
Engine temp: (w/160* thermostat) 160-165 most of the time, it may rise to 175 after coming off plane…
I think you may have a low raw water flow issue where it cools adequately at lower speeds but the extra heat load of WOT means a lot more heat has to be dissipated ….
 

Lou C

Supreme Mariner
Joined
Nov 10, 2002
Messages
12,671
PS
That Boss 302, well one of my best friends dad was a chief mechanic at our local Ford dealer. He & I checked out a brand new 1969 Boss 302 in the showroom it was $4600 USD on the sticker. June 1969. Just finished 8th grade summer of the moon landing & Woodstock! Same color combination! What’s it worth now?
 

Lpgc

Petty Officer 1st Class
Joined
Jun 17, 2023
Messages
258
The Mustang I pictured is a modified early 2000's 4.6, I like it a lot though.

Been on the boat again twice this week so far...

I previously mentioned the engine temperature swings, same again this week but not getting too hot now. Started out at light throttle with the temp fairly constant around 140, remained around the same on the plane at 30mph and even flat out, so I thought great. But then as usual after another run on the plane, slowing down the temp went very cold again dropping off the bottom of the scale (and the inlet manifold did feel cool so it isn't the gauge reading wrong). Got back to the mooring, removed the thermostat housing, spun the thermostat and blew through it, re-installed it and temp settled at 140 again... So the cool running is due to rust holding the stat open, it's becoming a pain with the stat sticking open so I'll be looking at ways to try to clean rust out of the engine cooling channels. The near overheat I previously mentioned is still a concern, can't see that being due to a stuck closed thermostat so will be looking at the raw water pump etc at some point but maybe over winter since there isn't much left of the season.

Also previously mentioned that if I ran the boat flat out it would start losing power, not misfiring but seemingly going lean so I think it's fuel starvation. The last time I used the boat this seemed to have got worse, it can now happen at slower planing speeds not only flat out. If I run it flat out it will now die/stall after a few seconds, at slower planing speeds it will go lower before dying/stalling, but the stall has become unrecoverable where-as before I could back off the throttle and the engine would keep running. I think I ruled out vacuum in the fuel tank / clogged breather because before a couple of runs I removed the fuel filler cap then tried immediately giving it some stick, the engine died after around the same amount of time whether I'd just removed the fuel filler cap or the cap had been fitted for hours before I gave it some stick. I'm thinking this could be due to clogged in tank strainer on the pickup tube, restrictive anti-syphon valve, clogged fuel filter / water separator, failing mechanical fuel pump, clogged strainer on carb inlet or something wrong inside the carb. The only other difference from the other day when it would only start to lose a bit of power after an extended run at full throttle is there is less fuel in the tank now. I doubt there's water in the tank now, there was at the start of the season but I removed it before first using the boat and since then I've run a few full tanks of fuel through it. What would you think is most likely the problem with fuelling?
 
Last edited:

Lou C

Supreme Mariner
Joined
Nov 10, 2002
Messages
12,671
As far as the 2 problems one the flaking cast iron I have had that but it hasn’t been chronic just a few episodes and I think it might be because I always filled the engine with good PG antifreeze for winterization (20+ years worth). I can tell it helps because when I start it after winter storage I see just the AF flowing out the exhaust followed by clear water not rusty water as I have seen with boats left dry for storage. If you can figure a way to flush the block with the drain plugs out that would probably help then fill with AF for winter storage.
If I repower this boat with a reman engine I will put a half closed cooling system on it, that eliminates this issue and also makes winterizing easier, and allows the engine to run closer to an optimal temp.
For the other issue I had the same thing on my boat and it was the anti siphon valve. My mechanic changed this way back in 2004 and I have had no more problems with it. I would start with that. They can clog, or corrode…
 

kenny nunez

Captain
Joined
Jun 20, 2017
Messages
3,290
There is a small fine mesh screen inside the suction tube. Pull the tube out and push the screen out with some wire or sometimes it can be blown out with compressed air.
 

kenny nunez

Captain
Joined
Jun 20, 2017
Messages
3,290
To prove out the problem set up a 6 gallon outboard tank so that it is easy to connect it to the fuel filter inlet. Run the boat until it starts slowing down then switch to the 6 gallon tank.
 

Lpgc

Petty Officer 1st Class
Joined
Jun 17, 2023
Messages
258
Thanks for all the tips.

I believe there's also a fine mesh in the fuel entry point on the carb but this should be clear as the fuel will already have been through the fuel filter?

I left the boat on the river, expect to use it again with family over the weekend but before then I should go myself and investigate this fuelling problem, check out the suction tube etc.

Should maybe also change the fuel filter. I don't remember the part number for my setup, can anyone help with part number?

Also, if I'm going to rig a small separate fuel tank it will be easier to use a separate piece of pipe between the small tank and fuel pump inlet. What size internal diameter pipe is it?
 

Lou C

Supreme Mariner
Joined
Nov 10, 2002
Messages
12,671
When I get home I’ll measure the barb on my spare fuel pump. As far as the water separating filter if it’s the one that the factory mounted on the block then it’s the OMC/Volvo standard size filters. I have spares of those too in the garage so I can post up the parts #s. I use either BRP or Sierra for those; the best are Racor with the metal water collection bowl. In my use I do change that filter yearly and when I dump out the contents in a glass jar it’s always clear fuel. Do you have straight gas where you are or are you mandated to use E10 as we are?
 

Lpgc

Petty Officer 1st Class
Joined
Jun 17, 2023
Messages
258
When I get home I’ll measure the barb on my spare fuel pump. As far as the water separating filter if it’s the one that the factory mounted on the block then it’s the OMC/Volvo standard size filters. I have spares of those too in the garage so I can post up the parts #s. I use either BRP or Sierra for those; the best are Racor with the metal water collection bowl. In my use I do change that filter yearly and when I dump out the contents in a glass jar it’s always clear fuel. Do you have straight gas where you are or are you mandated to use E10 as we are?
I looked on a UK marina's website for the fuel filter but there are a few that look the same https://repowermarine.com/buy-volvo...ne-engine-parts/volvo-penta-fuel-filters.html . This is the place I bought my Barr exhaust manifolds from and I think they'll know which fuel filter I'll need, just that I didn't phone them.

As you know, I bought the boat last year and did a lot of work on the engine but I didn't change the fuel filter. I did remove it and flush it a few times with petrol, didn't see any dirt in it at all. Earlier this year before using the boat I found there was some water in the fuel tank but think I got all the water out.

Obviously there's different brands of petrol but they're usually sold as 'regular unleaded' which is E10 and usually 95 octane or 'super unleaded' E5 in 97/98/99 octane depending on brand. I believe the octane ratings are on a slightly different scale to your scale, we use the RON (research octane number) rating while the US uses the MON (motor octane number) rating. Until recently we could buy super unleaded that was neat petrol. I convert vehicles to run on LPG (read propane) for a living, propane RON is around 110 but calorific value (heat you get by burning a set quantity) is a bit lower than petrol calorific value, though higher than ethanol calorific value.

Thanks for offering to check your spare filters but I've just come back to this after doing some real work (lol) and the marina is closed now so if I order a filter now it won't arrive tomorrow anyway. I'll probably be visiting the boat again tomorrow so I can just get the numbers off my filter and phone the marina while I'm there to check the numbers they say match my existing filter, thanks all the same anyway. If I phone the marina I can ask them if they have a compatible version that has the deeper water bowl.
 

Lou C

Supreme Mariner
Joined
Nov 10, 2002
Messages
12,671
if you have the original equipment fuel filter mount, I think this is what you need, this fits mine, I usually use the made in USA BRP ones, but the made in Taiwan Sierra ones work too.
I checked my spare fuel pump and there are no barbs on it, but I think the ID of the fuel line is 3/8ths of an inch, but better check to be sure.
See below for what filters fit that OEM mount. Racor is the best but most expensive…
 

Lpgc

Petty Officer 1st Class
Joined
Jun 17, 2023
Messages
258
Had to do 'real' work today but finished early enough to visit my boat on the river to try to fix the fuelling problem.

I took a 5 gallon jerrycan with intention of rigging a pipe to allow running directly from it to see if there was still fuel starvation. Immediately set about removing the engine cover and fuel tank cover to gain access to the top of the fuel tank. Disconnected the tank to fuel filter pipe at the fuel filter end, tried sucking on the pipe and found it difficult to suck fuel. So suspected a problem with the valve on top of the tank, removed the valve, it was difficult to suck/blow through it, found the ball bearing was stuck due to some black dirt/debris. Tapped the valve to remove the debris, re-installed it, tried sucking on the fuel pipe again and easily sucked some fuel into my mouth. Pretty sure I'd solved the problem I put the floor and engine cover back in, poured the fuel from the jerry can into the boat tank through the filler neck and went for a ride up the river. Success! No more fuel starvation when I give it some stick. I've not run it flat out yet because I had half the canopy fitted and it's still missing a rear support pole but I think it'll run fine at full throttle now. I had also recently been having some minor engine starting issues, it starts as normal again now.

Only a short ride this evening, mostly 7mph but also some 30+mph blasts. The engine temp remained close to 140 throughout, but I did clean the thermostat after last using the boat.

Was thinking great, time to zip the cover back up and head home, will be using the boat again on Sunday with family. But then found the tilt/trim would go up but not down lol. Fixed that problem too, turned out to be just a bad connection in the round 3 pin multiplug.

Incidentally, iIrc the valve on top of the fuel tank was previously described to me as an anti excess flow / anti-syphon valve, but I found mine is a none return valve. I suppose it could be described as an anti syphon valve because it's there to prevent fuel going backwards from the filter back to the tank, but it's not an anti excess flow valve.
 

Lou C

Supreme Mariner
Joined
Nov 10, 2002
Messages
12,671
It’s really a safety device. If the fuel line from the tank to the filter/pump ruptures that valve prevents fuel from siphoning out of the tank into the bilge. Particularly important if the top of the tank is higher than the level of the filter/pump. As I mentioned I had the same problem & the mechanic I was using then (great guys factory trained OMC & Merc) replaced it with a better quality brass one instead of the alu one that Four Winns had installed when it was built in 1988. That was replaced 20 years ago no further problems. So glad that you got it! Success!
 

kenny nunez

Captain
Joined
Jun 20, 2017
Messages
3,290
The purpose was to stop fuel flow in case the fuel line started leaking between the tank and engine. Somewhere there is a vacuum specfication on them that so many inches of mercury to lift the ball. The aluminum ones were bad on the ball getting stuck. The solid brass ones are the best.
Is your Mustang left or right hand drive? Manual or standard.
 

Lpgc

Petty Officer 1st Class
Joined
Jun 17, 2023
Messages
258
The purpose was to stop fuel flow in case the fuel line started leaking between the tank and engine. Somewhere there is a vacuum specfication on them that so many inches of mercury to lift the ball. The aluminum ones were bad on the ball getting stuck. The solid brass ones are the best.
Is your Mustang left or right hand drive? Manual or standard.

I removed my aluminium valve the other day, it definitely works as a none return valve to prevent fuel flowing backwards from the filter to the tank but I don't think it would prevent fuel syphoning out of the tank into the bilge in case the rubber hose broke off from the fuel filter.

It's not my Mustang, it's one of my customers. It was originally left hand drive but was converted to rhd before I first saw it so at least before a couple of years ago. It is now manual but I don't know if it was originally manual or auto. I do know the owner's had lots of other mods done to it, including engine and exhaust system mods. Not sure if the same owner's Jeep SRT is pictured in one of the Mustang pics I posted but I had that in the yard at the same time as the Mustang. He also owns a supercharged SRT Jeep and other SRT stuff like his 300C but I think the 300C is just the 5.7. This coming week I am converting his friend's 1970's pickup to run on LPG.

Going for another ride on the boat tomorrow, just on the river again. Really wanted to use the boat on the sea, lakes and lochs this year but around the time I was planning it the weather wasn't great so decided not to go, think I missed the opportunity to use the boat elsewhere this year.
 

kenny nunez

Captain
Joined
Jun 20, 2017
Messages
3,290
Looks like your customer has some deep pockets.
What are the speed limits in the canal locks? I guess high speed trimmed out bass boats with transom jacks would be frowned on.
The wife and I watch a lot of Brit Box murder mysteries and quite often a mystery is centered around one of them.
 

Lpgc

Petty Officer 1st Class
Joined
Jun 17, 2023
Messages
258
Looks like your customer has some deep pockets.
What are the speed limits in the canal locks? I guess high speed trimmed out bass boats with transom jacks would be frowned on.
The wife and I watch a lot of Brit Box murder mysteries and quite often a mystery is centered around one of them.

Not sure about canal speed limits but would guess speed limit on a canal is around 7mph. The only time I've been on a canal boat was as a 6 year old on a school trip. Not sure which murder mystery films / series you mean.

I've been using the boat on the river Ouse which runs through York. There's a 7mph speed limit on the none tidal stretch of the Ouse I've been using but once you get away from moored boats and fishermen the speed limit isn't really enforced and plenty boaters 'blow the cobwebs' out of their boat engines.

A short distance from where I launch on the river there's a weir, it's tidal South of the weir and speed limits are a bit higher on the tidal section. There's a lock to get between the tidal and none tidal sections but I've never used the lock or been on the tidal section of the Ouse. The tidal section runs through a few other towns such as Selby before running into the river Humber which runs out to sea on the East coast, can get to the sea from where I've been using the boat after maybe 60 miles.

There's all types of boats moored on the none tidal section of Ouse, a minority are canal boats but mostly 30/40ft cruisers people use as weekend homes. A lot of owners will only ever use their boats on the river but some will take them out to sea and visit sea ports in the UK and abroad.

My dad and his friend both had 40ft sailboats, dad's friend's boat was moored somewhere in Spain, they sailed it from Spain to France to Guernsey, Jersey, Isle of White then into Portsmouth. That was a sailboat but they could've done the same trip in a large power boat, then gone from Portsmouth with stops at other ports, up the Humber and eventually moored on the Ouse near York. Dad's friend went further than that, sailed North past the humber and moored his yacht at Scarborough.

I don't think any type of boat would be frowned on but they wouldn't appreciate speeding past moored boats. There will be some quick boats on the river but most of them will be there only temporarily after coming inland from the sea via the humber.

Missed my chances for using my boat on the sea this year but will get there next year, more likely the West or South coast than the East coast unless I launch on the river near York and follow the river down into the humber and out to the East coast.
 
Top