Do I have a blown head gasket

[skipmac]

I think I do. Engine is a Westerkeke W58 which is a Perkins 4.154 with red paint. Recently it started losing water from the fresh water system and I don't see any obvious leaks.

I topped off the header tank, ran it at the dock for 10-15 minutes and had to add a pint. Same thing a couple of times looking for the leak. Yesterday ran it about 20-25 minutes and had to add over a quart.

Also, seems to be running a little warmer than before. Gauge shows around 200 F. A handheld temp gun showed +/- 204 on the thermostat body. I think previously is was running more like 190-195.

Final symptom, seems a little harder to start, initial turn over a bit slow and has to turn over a couple of times before it fires where previously it fired immediately.

So do I have a blown head gasket? Probably? Any reasonably easy, non destructive, minimal disassembly test to confirm?

AND if yes, how big a job is this for a reasonably skilled DIY mechanic that hasn't done a head job before? Any major pitfalls, special tools or special skills needed?

[thomm225]

The engines I've had that blew head gaskets allowed the cooling water to mix with the oil making it a milky grey color

I'm sure it could blow the other way also, but you may want to closely watch the engine for leaks when you test run it before doing a replacement

The last engine that blew a head gasket I owned was the Bukh 10 Diesel on the Bristol 27 I have now.

[skipmac]

Originally Posted by thomm225

The engines I've had that blew head gaskets allowed the cooling water to mix with the oil making it a milky grey color

I'm sure it could blow the other way also, but you may want to closely watch the engine for leaks when you test run it before doing a replacement

The last engine that blew a head gasket I owned was the Bukh 10 Diesel on the Bristol 27 I have now.

Oil is clear and clean. So far no milky look at all.

It does seem like with the compression in the cylinders that it would blow the other way and put oil in the cooling water or water in the crank case oil but so far no obvious evidence of either.

Also, no smoke or steam out the exhaust.

[model 10]

Your problem sounds just like the one I had with my Perkins. Run the engine with the cap off the tank and look for some bubbles to confirm the problem.
I managed to change the head gasket in one long day but then you need to re-torque the head and that is a pain. If I were to do the job again I would not install the water tank or the oil filter mount before running the engine to warm it up for the re-torque.

[skipmac]

Originally Posted by Ecos

Your problem sounds just like the one I had with my Perkins. Run the engine with the cap off the tank and look for some bubbles to confirm the problem.

Will give that a try, especially since it's an easy test (always try the easy stuff first just in case) but since the water is going out I'm thinking I won't see bubbles coming in?

[Teknishn]

Originally Posted by skipmac

"Oil is clear and clean. So far no milky look at all.

It does seem like with the compression in the cylinders that it would blow the other way and put oil in the cooling water or water in the crank case oil but so far no obvious evidence of either.

Also, no smoke or steam out the exhaust."

"Also, seems to be running a little warmer than before. Gauge shows around 200 F. A handheld temp gun showed +/- 204 on the thermostat body. I think previously is was running more like 190-195."

Based on the above it doesn't sound like an engine problem but rather, possibly, a leak in your heat exchanger/condenser and you are losing your cooling water over the side through said leak. The harder/slower starting may or may not be related. Just my thoughts...

[model 10]

No, the gases will blow out of the cylinder into the water. Even with a leak, there is way more pressure in the combustion chamber than the cooling system.

[skipmac]

Originally Posted by Ecos

No, the gases will blow out of the cylinder into the water. Even with a leak, there is way more pressure in the combustion chamber than the cooling system.

Well that's what logic indicated to me. Pressure inside the cylinders is way, way higher than pressure in fresh water system. So where the water going? I've looked pretty closely and I don't see steam coming out from under the cap, around the hoses or anywhere else.

[Woodland Hills]

Check your bilge. The combustion gasses may be pushing the water out the overflow at the cap or overfilling the coolant recovery bottle.

[Greg Mason]

My Perkins made water in the expansion tank, and it wasn't clear. It was the head gasket.

[deblen]

Suggest reading the service manual first before teardown. It may help avoid dropping parts & other possible "mistakes" / Len



https://www.westerbeke.com/technical...ech_manual.pdf


Suggest you do a pressure test on fresh water system first.
There are a zillion brands-this is an example.
https://www.amazon.com/Radiator-Pump.../dp/B009RIUE0C

[DougR]

There are lots of ways a bad head gasket can leak....
-coolant into the oil
- compression loss from one cylinder to an adjacent cylinder
- coolant into a cylinder
- compression into the coolant
- etc.

You could go to an auto parts store and get a test kit which will show the presence of CO2/combustion gasses in the coolant, a sign of a gasket leak. You could also get a pressure test kit which pressurizes the coolant system and allows you to check for leaks which might be in the heat exchanger or perhaps a cracked exhaust manifold.

Something to do before pulling the head off...

DougR

[skipmac]

Originally Posted by DougR

There are lots of ways a bad head gasket can leak....
-coolant into the oil
- compression loss from one cylinder to an adjacent cylinder
- coolant into a cylinder
- compression into the coolant
- etc.

You could go to an auto parts store and get a test kit which will show the presence of CO2/combustion gasses in the coolant, a sign of a gasket leak. You could also get a pressure test kit which pressurizes the coolant system and allows you to check for leaks which might be in the heat exchanger or perhaps a cracked exhaust manifold.

Something to do before pulling the head off...

DougR

Oh absolutely. I really, really don't want to pull the head off until I'm sure.

Thanks for the suggestions on the tests. That's on my list for Monday.

[tml]

A pin hole leak in a hose can be very hard to see particularly if it is against the engine. Had one years ago and could not find it.
The answer was a NAPA florescent dye kit which comes with goggles and a small flash light that makes the dye glow in the dark. Even if the water is evaporating as it hits the engine it will leave a glowing dye mark. Don't remember what it cost but it was modest.
Tom

[Jason Flare]

Originally Posted by Woodland Hills

Check your bilge. The combustion gasses may be pushing the water out the overflow at the cap or overfilling the coolant recovery bottle.

Originally Posted by Greg Mason

My Perkins made water in the expansion tank, and it wasn't clear. It was the head gasket.

My expansion tank began slowly filling up. I tasted the water, (Just a drop,!) and
it was salty.

Engine ran fine otherwise.

I diagnosed it as a leak in the heat exchanger and replaced that. It’s been fine since.

As far a losing coolant from the closed loop side I would still suspect the heat exchanger provided the engine has no other major symptoms.

It is my understanding that coolant can pass to the raw water side and vice versa depending on where the leak is and what the pressure of each loop is.

For axample, in a car, oil can get into the coolant and coolant can get into the oil depending on the pressure of each loop at the leak.