Closed Cooling System on Port Engine Running Hot(ter)

[tpenfield]

My plan for next weekend (Labor Day Weekend ( in the USA) ) summer gone by already

I want to see if I can get a visual on the nose/fitting that comes through the transom assembly. My understanding is that there is a plastic insert that expands the intake hose to make a tight fit to the transom assembly ( similar to, but not identical to, the hose attachment at the bell housing). The fitting on the inside of the transom assembly seems to be a right angle, so getting my bores ope through there may not be possible.

The boat is in the water, so I am wondering about the ability to take off the right-angle fitting to get a good look at a possible Bravoitis situation. Water will be coming into the boat while I do this, so I will need to work fast, hope the bilge pump keeps up, and maybe stuff a rag into the opening if I get delayed.

Any thoughts about doing this?

If I am lucky, there will be a really low tide exit weekend and the boat will basically be resting on the bottom then, which would be a perfect situation to do this sort of thing.

 

[alldodge]

I see that as a bad move. If you put muffs on the drive, maybe wrap thin plastic around the drive, it can slow it down. The hose enters just above the drive shaft boot, and I'm pretty sure your water line is above it. I just installed the Bravoitest fix on my Rinker, so here is the pic of where the hose comes in.

 

[tpenfield]

Yup, I guess things can go badly real fast. I'll be working from inside the boat just to get a visual on if the inlet hose is restricted in that area. I suppose I can do my best to get a look with the borescope and not take too many things apart.

 

[alldodge]

If you remove the end from the pump, is you bore scope long enough to go down the length of the hose to the drive fitting?

 

[tpenfield]

If you remove the end from the pump, is you bore scope long enough to go down the length of the hose to the drive fitting?

No probably not long enough there is also a sea water strainer in between the transom inlet and the sea water pump. . . besides, when the borescope reaches the fitting on the inside of the transom, it is a pretty sharp bend (right-angle bend) so the borescope will just get stuck at that point.

I am hoping that if I remove the hose leading to the strainer/sea water pump, I can get the borescope into the right angle fitting enough to see if it is blocked by corrosion expansion. The end of the borescope that I have has a rigid end to it . . . about 2" long. If it were flexible all the way to the camera/light lens, then it would be no problem

 

[tpenfield]

I did take some pictures during the day, so I thought that I would post a few . . .

unbuttoned the intake plenum and some of the closed cooling system to access the fuel pressure regulator, which is on the forward part of the fuel rail


Here are the old and new (silver) regulators and the plug fitting that connects the discharge vent to the return side of the fuel rail.


Here is the new regulator installed


Pressure tested at 34 psi and held.

Then it was a matter of putting the engine back together and testing it out.


Pretty much the same temperature difference as before. At no wake speeds the port engine will touch 170 at times . . .

At cruising speeds (2800 rpm - 30 mph) the temps are within 10 degrees.


When I bring the boat up to 3400 rpm (38 mph) the port engine rises up to the 175 range.

so, after all that fuss getting a new fuel regulator and still having the issue, I said ahhhwww-frig-it and went and got some gas and a pump out and . . . Then headed to the beach. :thumb:

 

[HT32BSX115]

Hey Ted,

You know, before you take anything apart again, how about trying a raw water FLOW test? Disconnect the raw water hose from the heat exchanger right after the oil/PS cooler at the heat exchanger raw water inlet.

Connect it to a large hose (at least as large as the hose going to the HE) AND run it into a 5 gallon bucket and time how long it takes to fill it at say, 1000 RPM. Do this on both engines to compare.

If the hotter engine side fills slower than the cooler one, there's a restriction in the raw water supply system of the hotter side.

If it's the same, the look to either block/head/circulating pump issues or riser/exhaust Y-pipe restrictions etc.

I think it's gonna be something simple.

 

[tpenfield]

Hey Ted,

You know, before you take anything apart again, how about trying a raw water FLOW test? Disconnect the raw water hose from the heat exchanger right after the oil/PS cooler at the heat exchanger raw water inlet.

Connect it to a large hose (at least as large as the hose going to the HE) AND run it into a 5 gallon bucket and time how long it takes to fill it at say, 1000 RPM. Do this on both engines to compare.

If the hotter engine side fills slower than the cooler one, there's a restriction in the raw water supply system of the hotter side.

If it's the same, the look to either block/head/circulating pump issues or riser/exhaust Y-pipe restrictions etc.

I think it's gonna be something simple.

I think so too . . . Just wondering about running the engine for a minute or 2 without water going to the exhaust :noidea:

 

[alldodge]

Maybe the thing to do is enjoy the boat until it needs to be put to bed for the winters nap. Then look into the other issues

 

[tpenfield]

Maybe the thing to do is enjoy the boat until it needs to be put to bed for the winters nap. Then look into the other issues

I've been thinking about doing just that, now that September is upon us. We will probably use the boat a handful more times this season

Labor Day
Vineyard trip later in September
Maybe end of September

I do have a bunch of holidays coming up in October . . . but often the weather is colder. So, I could dedicate some of that time to diagnostic work with the boat out of the water.

I think that I will check for Bravoitis and leave it at that.

 

[HT32BSX115]

I think so too . . . Just wondering about running the engine for a minute or 2 without water going to the exhaust :noidea:

Well, if it's in a slip with a "washdown" water supply, you could hook the washdown hose up to the HE connection so there'd be at least some water coming out of the risers to keep the rubber parts wet.

If the raw water flow at 1200 rpm is being restricted enough going into the HE to make the engine run noticeably hotter, the (lower) flow might be noticeable too in the form of longer time to fill the 5 gal bucket etc. At the same time, if there's restriction from the HE to the risers, it would also manifest itself in the form of high raw water pressure at a given RPM. (can't remember if you compared raw pump pressure on both sides)

 

[tpenfield]

Well, if it's in a slip with a "washdown" water supply, you could hook the washdown hose up to the HE connection so there'd be at least some water coming out of the risers to keep the rubber parts wet.

If the raw water flow at 1200 rpm is being restricted enough going into the HE to make the engine run noticeably hotter, the (lower) flow might be noticeable too in the form of longer time to fill the 5 gal bucket etc. At the same time, if there's restriction from the HE to the risers, it would also manifest itself in the form of high raw water pressure at a given RPM. (can't remember if you compared raw pump pressure on both sides)

I am on a mooring, but could I go to the town dock and hook up to the water there. Overall, a good idea.

You guys are helping me think outside the box, so that is great. All to often, when dealing with something for this long you tend to get tunnel vision.

Continual input from you guys is a good thing :thumb:

 

[Fun Times]

On your next cruise out, try connecting the scan tool device you have and read the temps the ECM is reading vs the gauges as typically you'll see two different sets of numbers due to different sensors being used. As long as you are not exceeding 179.9+ temps at all speeds, you should be good to go. If the starboard engine is slow to react to rising temps of under 179.9, install a new thermostat in the starboard engine and go for another cruise with the scan tool connected....The warm up time frame should even out with the other (port) engine. The 179.9 is a little extra leeway for warmer bodies of waters you may ride in....Nothing really wrong with seeing mid 170's on the gauges + the scan tool images you posted earlier in the topic didn't seem to show a heating problem, just a running too cool problem on the other engine... http://forums.iboats.com/forum/engi...ngine-running-hot-ter?p=10252673#post10252673

Glad you worked hard at getting the fuel pressure back within specifications though as that was important. Liked your test of the regulator before installation as that really was a good idea to do.:thumb:

 

[tpenfield]

Thanks Fun Times . . . I do believe that the gauges read a bit higher than what the ECM(MEFI) is showing, maybe by about 5-7 degrees. I think the fuel pressure and lean looking plugs were just a bump in the road, but certainly a good thing to fix.

I assume that the alarm is going to sound at about 190-200 degrees F. The engine has touched 180 F per the gauge, a few times, but not gone over. So probably the ECM was seeing 175 at that point. The alarm sender is at the t-stat housing, whereas the temp sender is on the by-pass loop at the recirculating pump. So, the running temperatures are probably a bit different at those 2 locations.

I'm sort of thinking it is 'Bravoitis', and an associated reduction in the raw water flow, but a visual inspection will need to be done to confirm. My IR temp gun sampling did not really point to that, but it may have to do with how the coolant recirculates within the engine block, versus goes out to the exhaust manifolds.

I have seen a retro-fit kit on the web to remedy Bravoitis. Not sure if that is the preferred route versus just fixing the corrosion around the intake tube attachment point. Anyway, I'll be trying to confirm either way if it is Bravoitis and what the difference in raw water flow may be between the 2 engines, then take it from there.

If I keep the engine(s) under 3K RPM, I'm fine and usually that is plenty fast for the typical sea conditions. This hopefully will get me to the end of the season, and I can have the boat on the hard to work on from the outside.

So, next steps are to try to get a visual inside the intake fitting at the transom assembly within the engine bay.

 

[nola mike]

Where on the cape are you Ted? Sounds like I may need to pay a personal visit, keep an eye on one set of gauges, help with navigation to the vineyard, etc.

 

[tpenfield]

Where on the cape are you Ted? Sounds like I may need to pay a personal visit, keep an eye on one set of gauges, help with navigation to the vineyard, etc.

Well without divulging too much detail on the Internet, I'm not sure why you would come all the way from VA for lil' old me :noidea: Although I appreciate offers to help. :thumb: I do go to the Vineyard a couple times a year. Have not been over there yet, since the boat has been a little 'iffy'. But if you are in the neighborhood, send me a PM.

 

[nola mike]

Lived in the Vineyard for a while, spent some formidable years in Falmouth, dad lives in Mashpee. I'd come for the D'angelo's and Dunkin' Donuts.

 

[tpenfield]

Lived in the Vineyard for a while, spent some formidable years in Falmouth, dad lives in Mashpee. I'd come for the D'angelo's and Dunkin' Donuts.

:thumb:

 

[tpenfield]

Looks like T.S. Mermine is going to give us a so-so weekend for Labor Day

I found (forgot that I had) a smaller & more flexible borescope/endoscope that I can hopefully do an endoscopy on the raw water intake hose to see if it looks like Bravoitis. I hope to get a look either today/tomorrow Monday (Labor day) is supposed to be somewhat wet.

BTW - I 'bench tested' the original fuel pressure regulator. It holds pressure at 30 psi and starts to leak pressure at 32 psi.

 

[tpenfield]

Update from on the water in Buzzards Bay

I took the intake hose off that leads from the transom assembly to the sea water pump and put my endoscope into the fitting to see if I can get a look at the external hose fitting for signs of Bravoitis.

My scopes could only get a partial view of the hose due to the nearly right angle bend in the inside fitting. I could see the far edge of the hose and the plastics insert that binds it in place. The hose looked ok and the plastic insert looked intact. I need to get a better view of the entire fitting connection, but probably will wait until the boat is out of the water to do that.

Bottom line - no obvious signs of Bravoitis.