Ever-Popular Overheating Perkins 4108

[CSY Man]

I have put in a new heat exchanger and thermostat. That did not solve the problem. My diesel guy has told me that it is common for the Perkins 4-107/108 to overheat and he recommends a larger heat exchanger. I like the post about replacing the exchanger with a Perkins 4-236 heat exchanger.
Kinne

Agree with all of the above and have done the same except the larger heat-exchanger..Can't fit it in the tight space back there...

[kinne]

Originally Posted by CSY Man

Agree with all of the above and have done the same except the larger heat-exchanger..Can't fit it in the tight space back there...

The nice thing with the Gulfstar is it has a huge engine room, I found a heat exchanger made by seakamp that has two tubes, but I am not sure if I can mount it it the present location, which is under the oil filter. Does anyone have a source for the Perkins 4-236 heat exchanger?
Kinne

[jlogan]

I haven't bought from these folks, but they seem to have Perkins heat exchangers...let us know how it works if you do business with them.

Heat Exchanger - Perkins 4 & 6 Cylinder Models

[CSY Man]

The nice thing with the Gulfstar is it has a huge engine room,

You are not kidding, there is enough room there for the Mother in-law's bunk...

[Maddog]

I also have a 4-107 that use to have an overheating problem. Turns out I had a cronic air lock at the top of the head. When ever I replace the coolant, I also remove the sensor to vent the head and add a little coolant there as well. I have not had a problem since.

[jlogan]

Lots of room in the Gulfstar engine room, except in the GS 37, you have to be 3' high to use it!...most of my work is stretched out in the cockpit locker with most of my body on top of various sharp parts working on the engine....that is if you are small enough to get through the cockpit seat (lid) to get into the locker in the first place. I am convinced this is why Gulfstars are sold as the owners get older...they can't work on their boats because they can't fit into the locker....

[Chief Engineer]

also, if you are using the engine to heat water in a water heater, one must be very careful that that line does not air lock also.

Originally Posted by Maddog

I also have a 4-107 that use to have an overheating problem. Turns out I had a cronic air lock at the top of the head. When ever I replace the coolant, I also remove the sensor to vent the head and add a little coolant there as well. I have not had a problem since.

[marc2012]

I did not think there was that much difference between the 37&41.If have only engine cramped,add water maker.inverter.fridge ets,NO ROOM.

[over40pirate]

I fought overheating problems with my 4-107 Perkins for 3 years. I would clean the heat exchanger with muriatic acid and we would be good to go for another 6 months or so. Then after doing this 4 times, it didn't fix it. I replace the raw pump cam and turned the cover over, and it didn't fix it. A diesel mechanic told me to replace the heat exchanger. I cleaned it again. It lookes like a shiney penny, and the tubes all looked good. same problem. Boiled over at more than 1/2 throtle operation. Finally I borke down and replaced the heat exchanger and that cured it. I sure wiish I had done it in the begining. It would have saved me from crossing the Gulf streem with the dink tied along side and running for 45 minutes, running the diesel for 15 minutes, etc, etc, etc, untill we got back to FL. Wheres the wind when you need it?

I wouldn't replace the raw water pump, unless the bearings are shot, and even then, I'd rebuild it. It's a basic pump. The impeller, and cam are easy to replace, and turning the cover over, or replacing it are no big deal. Thats about all there is to the pump, besides a shaft, bearings and seal.

[easterly]

Go to Autozone and buy Redline water wetter. It will lower your operating temps. I use it on turbo and supercharged cars.

[jlogan]

I've had it...I don't care how much trouble it is and or how much it costs to fix, I'm going to have a Perkins 4-108 that runs at the proper temperature. I've been working on this since I got the boat. Since I just day sail mostly, it is not a big problem, but it has run me nuts. The latest twist is now that the temp gage seems to run hotter and hotter - up to 230, but the alarm doesn't go off and the engine (and I have experience with diesels) doesn't seem hot or act like anything is wrong - you can still lay your hand almost anywhere on the engine when it is operating...New plan: I am going down this list until I fix it. I'll stop when the problem goes away.

1. Replace temp sensor and gage

2. take off every hose to every piece of cooling gear on the engine and make sure that it is clear..I don't think this engine has ever had a disintegrating impeller, but I'm going to find out. Part of this will be backflushing all the cooling system with pressure.

3. Pull the hose to the cooling elbow and check it..although water flow out the exhaust seems ok, and there is no steam being produced in the exhaust flow.

4. I've cleaned the Heat Exchanger, and it looks ok inside, but I'll replace the heat exchanger.

5. New thermostat..don't think this is the problem, but....

5. New Water pump - anyone know the flow rate for a G65 Sherwood as used on the Perkins? i.e., how many seconds to fill a 5 gallon bucket or some such rule of thumb?

6. New Transmission Oil Cooler - Long shot, but if I've done all of the above.....

7. New Yanmar............


Any suggestions, additions, or comments on the list above will be appreciated....

[GordMay]

See:
http://www.cruisersforum.com/forums/...sting-645.html

[svHyLyte]

Your sensor may simply be defective. Obtain one of these: Celestaire, Inc.: Infra-red Thermometer and use it to check the temperature of your system at the sensor. It's a handy tool to have around.

FWIW...

s/v HyLyte

[SkiprJohn]

Aloha jlogan,
It probably is your sensor and gauge if the engine is not hot to touch. Most overheating complaints are caused by many of the things already covered and the biggest culprit is too big of prop or too high of pitch.
Kind regards,
JohnL

[Chief Engineer]

I agree with getting a small handheld infrared heat gun.

You can use them for lots of things....just don't look into the laser pointer.

I use a Raytek