In Boat Head Gasket Replacement

[meyermm]

Hellosailor - your going to get into trouble writing comments like that but I agree for what its worth

[Extemporaneous]

How's this unit look?
Will it do the job?
May need to find the right adapter for your engine though.

Extemp.

[hellosailor]

Meyer-
Trouble for what? Alleging that there are boatloads (staying on topic) on incompetent shops & mechanics, or worse? If that's against forum policy, I guess telling people "don't step on that landmine" or "that's a shark warning flag, don't go swimming here" is wrong too. Won't stop me from saying it.

[Lancerbye]

I totally agree with your earlier comments about having real trouble shooting done at the dealers. The problem I see often is that the old experienced service managers and mechanics have retired and are out cruising. These have been replaced by college trained, book smart and practical not so smart, technicians. They are trained in the art of parts replacement and know how to use the latest software in dertermening the cost of the replacement job. They only know how to follow a path of replacing parts until the problem goes away. It's not really their fault, this is what they are being taught. You can not make a 30 year experienced mechanic in 2 years. We will all pay the price for not having kept up training over the years and did not get enough apprentices trained. The whole world is now short of experienced trades people. So the inexperienced service type is what we are left with.

[meyermm]

Originally Posted by Extemporaneous

How's this unit look?
Will it do the job?
May need to find the right adapter for your engine though.

Extemp.

Ye that is the unit but remember you need compressed air to use it as well as the adaptor. The adaptors they usually are supplied with are for spark plug insertion point.

[Chief Engineer]

Some leakdown tests can be performed by removing the glowplugs...if so equipped.

I have made my adapters from old injectors e.g. Yanmars have a variety of bottom pieces that go into the head with basially the same upper part.

As far as the previous comments....the best have no problem providing references.

I have been to a number of schools and have never heard about throwing parts at things.......Time alone does not make an experienced mechanic; as my first Port Engineer said, "when workin with another guy who has more experience than you, steal every thing you can...knowledge that is".

When I started at a Tug Maintence outfit, they called me "College Boy" because I am...with two degrees....and I was always referring to manuals. I was the smalles guy there in the shop by (60 lbs) needless to say, I got some of the really "fun"
jobs in bilges/tanks and double hulls.

[hellosailor]

"You can not make a 30 year experienced mechanic in 2 years."
Don't make it sound like someone flipped a switch and changed the crews. For the past hundred years, every time a mechanic has retired, someone else was promoted and some newbie got a job starting on the bottom rung. In three years you've got a mechanic with three years experience, two years later he's got five years...and 29 years down the line he's gonna retire too.
The problem is more along the lines that there have always been too many rubes, too much money and people who are willing to ante up and not complain (we're taught in grade school to be good droids and not complain) if the problem wasn't fixed. Some problems ARE incredibly difficult, but there are an awful lot of alleged mechanics who just aren't very sharp. Certified or not.
The same way that motorists on Route66 used to have their radiators and shocks replaced by outright thieves, who still play the scam on I95 and I80 and other places where they can readily shear the sheep.
And that's not my opinion--that's the finding of many consumer affairs office, investigative reports, and attorney generals who have caught them and convicted them, year after year. Boat mechanics? Maybe better, maybe more honest, but they're still only human.

[Cheechako]

A 'blown" head gasket can be as small as a minor etching in the block or head from engine acids etc between cylinders or between a waterway and the cylinder. I took the head off my Perkins 4-108 once (for other reasons) and when I got everything cleaned up I noticed that one small area from a water passage to cylinder #3 was lower by maybe 3 or 4 thousanths than the rest of the head surface. With the cleaned up surface of the head, this showed up as a dark spot. It had obviously been leaking for a long time, but no engine symptoms were apparent. maybe it only leaked during warm up until the engine warmed up.
If you are losing (or think you are losing) as little as 4 0unces., I would not add any coolant and check it daily while using the engine, do this long enough to convince yourself that you are not losing the minor amount due to expansion out the cap relief etc. You will know eventually if you are really losing coolant inside somewhere.

[JArcherM]

Absolutely can be done in the boat.

As to everyone about testing etc....

Get a leakdown tester. Many times you can not find a head gasket leak with just a coolant pressure tester. You are talking a leak that only shows when hot or with tons of pressure during combustion. It's going to take more than a few psi to find your issue.

I use a scuba tank and fittings to get to a leakdown tester. If you have a head gasket leak the myth is you will always see coolant in the oil or white smoke. Not true. What you will see is bubbles in the header tank when you pressurize the offending cylinder.

A simpler trick is to take the overflow bottle off the overflow hose and squeeze a glove or bag around it. Run the engine and you will see the glove start to inflate. This is not conclusive, but can give you a little more evidence to start moving in the right direction.

When my clients have had two or three mechanics come in and attempt repairs on a no start, or overheating issue, it is usually the leakdown tester that gives me the answer.

The art of diagnosis is long gone it seems.

Other causes of coolant loss....
Hot water heater - bypass and recheck/ pressure test while isolated.
Heat exchanger rot out by the elbow - remove elbow and inspect
Loose hose clamps.... Like very slightly loose causing a single drip. Inspect very carefully
Bad Radiator cap- test
Oil cooler - after letting the engine sit overnight, pull the dipstick banjo on the bottom of the he pan, take some oil out and let it sit in a clear cup. Look for water.
Cracked head - good luck. Pressure test and look up the exhaust of the heatexchanger. Leakdown test. Teardown. Machine shop etc.

There are more but these are common.

[skipperpete]

Since the earlier posts were in early 2009 I think it might already be fixed but I agree with your approach to engine diagnostics, a process of informed elimination and yes, yet another lost skill in the industry. With the advent of common rail engines and total ECU control, diagnostics have become the realm of the engine manufacturers software program, if the program is unavailable we’re reduced to swapping sensors and doing leakage tests ( cylinder and injector).

[JArcherM]

Originally Posted by skipperpete

Since the earlier posts were in early 2009 I think it might already be fixed but I agree with your approach to engine diagnostics, a process of informed elimination and yes, yet another lost skill in the industry. With the advent of common rail engines and total ECU control, diagnostics have become the realm of the engine manufacturers software program, if the program is unavailable we’re reduced to swapping sensors and doing leakage tests ( cylinder and injector).

For sure! I was posting for all the folks that reference this. My last two boats were touched by several other technicians and lots of wasted money and time had a little diagnostic work been done.

People are quick to think if there is no water in the oil, or your not low on coolant that it is impossible to have a headgasket failure.