Oil pressure loss

[pr2501]

On my 4.108 ED22195U oil pressure went down. I think i have worn bearings.
I had an accident and i was laying on side and running engine to get back in deeper water.

Now i am back at home, but my plan is to go back on my boat in Guatemala in January.

I need to know if can i replace baring without taking engine out?
Do i have to use a special tool to remove oil cover and bearings from crank shaft?

I have experience doing this on cars. Lets presume that bearings are still original.

Thank you

[Lepke]

Room to work may be your biggest problem. If it's a sailboat you may need to pull the engine. If you pull the engine, I would rebuild it.
If you have auto tools, wrenches and a socket set, you should have most of what you need to change bearings.
You pull the pan. Except for fixing damage, most marine engines have standard bearings, but the bearing is marked. My 65 year old Detroit Diesels have standard bearings. It could be more than bearings. Look for damage on the crank journals. Also remove the oil pump and look inside for damage.

How low is the oil pressure? How long and at what rpm did you run?

If you're not smoking your rings may have had enough oil. If it was my engine I would replace the main, rod, thrust bearings and the oil pump. If it smokes, I would do a rebuild. Other damage could include cam bearings, lifters, rocker arms, timing gears and bearings, fuel pump gear, etc. It all depends on what the oil pressure was and how hard the engine was working.

If the gearing is damaged you may have other internal damage that an overhaul won't fix.

[model 10]

I sent you a PM.

[pr2501]

Thank you.
I did also also answered to PM.

When i was in Gutemala i did noticed that they have in many cases price double as they were in America.

That worries me also.
But,...

Do you know where can i find some manual or data sheet about bearings. I would like to have also an idea before opening the engine.

[pr2501]

"most marine engines have standard bearings" (Lepke)

But it confuses me that car crank shaft can be honed, and then you have to buy bearings of different dimension. So what about boats?

[model 10]

Originally Posted by pr2501

"most marine engines have standard bearings" (Lepke)

But it confuses me that car crank shaft can be honed, and then you have to buy bearings of different dimension. So what about boats?

The Perkins crankshaft has hardened surfaces. It's not common to have the equipment around to re-harden the journals. You put the crank in an oven, heat it red hot in cyanide gas. I think there is only 1 shop in all of California that can do it.
I also think TAD has some oversize aftermarket bearings.

[pr2501]

I do not want to do this job. It is that i was wondering if i can buy berings or wait to take old one down to see of what dimension they are. So if it is not comman to hone the crank, i can buy be the original one.

[sailorchic34]

If oil pressure dropped suddenly, it's not bearings. Bearing wear brings on a slow loss of oil pressure, unless you spin a bearing (Rare).

One thing to check is the oil pressure relief valve, which is a spring loaded bearing. if it fowls it can cause low oil pressure.

[jimbunyard]

Originally Posted by pr2501

On my 4.108 ED22195U oil pressure went down. I think i have worn bearings.
I had an accident and i was laying on side and running engine to get back in deeper water.

Now i am back at home, but my plan is to go back on my boat in Guatemala in January.

I need to know if can i replace baring without taking engine out?
Do i have to use a special tool to remove oil cover and bearings from crank shaft?

I have experience doing this on cars. Lets presume that bearings are still original.

Thank you

Almost certainly you won't be able to replace the bearings without removing the engine, there won't be enough room. Regarding tools, it depends on what you mean by 'special'. A large socket and a puller will probably be necessary for the crankshaft pulley.

There is a copy of the Perkins service manual here

http://www.endeavourowners.com/dscsn...p%20Manual.pdf

it will show you any special tools you may need.

A quick search shows main and rod bearings available in Std., .010", .020" and .030", so I assume the crankshaft can be ground. The hardening in most modern crankshafts is deep enough to allow regrinding without re-hardening.

As far as getting parts before hand, probably not a good idea. You need to evaluate what problems you have and what you need to address them, first, and then proceed accordingly. You should plan on new rod, main and camshaft bearings, as well as rings and oil pump (and of course overhaul gasket set) at a minimum.

The size of the bearing is normally stamped on the outside (non load-bearing side) of the bearing; i.e. STD., .010, .020....

The good news is that the 4108 is a very popular engine and parts are readily available and reasonably inexpensive. If I remember correctly Mitsubishi makes a variant of this engine, though I may be wrong in this. If so, and it turns out that you have the Mitsubishi variant, prices for parts may not be so economical...

[Nord Sal]

Dilution of the crankcase oil from a leaking injector pump seal can cause a loss of oil pressure.

[Cheechako]

At idle or higher rpm? My 4-108 was always low at idle.