Help!! More engine problems!!!!

[sebas54]

Sorry for asking so many questions. These are the problems that I experienced today. It's a 1988 gm 4.3l merc I/O alpha 1.

White smoke comes out of the breather tubes, excessively at high RPMs.

Oil drips out of the dip stick at high rpms(only sometimes). The oil looks clean.

I start to lose power when traveling at high rpms after about 5-10 min. The RPMs start to decrease.

One riser is hotter than the other.

Again I am sorry for asking so many questions it seems as if I bought a can of worms.

Please help.

What should I do?

 

[Limited-Time]

Re: Help!! More engine problems!!!!

Sounds like you have a lot of blow-by. The first thing I'd do is a compression check.

 

[PSS-Mag]

Re: Help!! More engine problems!!!!

I concur, my initial feeling is probably a burnt piston maybe a slipped piston ring.
A compression test well tell the real story.

 

[bomar76]

Re: Help!! More engine problems!!!!

maybe a slipped piston ring.

??????

Please explain exactly how a piston ring could "slip"......

 

[Coors]

Re: Help!! More engine problems!!!!

Maybe, the slip, that is worn under the piston skirt?

 

[sebas54]

Re: Help!! More engine problems!!!!

I did the compression test today and got 150 150 150 135 150 145

I also changed the oil and plugs and she ran better with liitle smoke and very small amount of oil leaked out of dip stick.


Now what??


Thanks

 

[Don S]

Re: Help!! More engine problems!!!!

The only way you could leak any oil out of the dipstick is to have crankcase pressure. Have you changed anything to the valve cover outlet ports that have hoses to the flame arrestor? Like putting in PCV valves instead of the proper fittings?

 

[sebas54]

Re: Help!! More engine problems!!!!

No, I actually disconnected the hose to the flame arrestor to keep that from happening. It didn't really help. Strange.

But the compression is good, right?

There wasn't much oil leaking today. Maybe I overfilled it, but why does it smoke out of the breathers. Is that normal?

 

[Fireman431]

Re: Help!! More engine problems!!!!

The cylinder @ 135 would cause me concern. Then I would look at the 145 cylinder. From a link I read, 148-152 is the range.

 

[Limited-Time]

Re: Help!! More engine problems!!!!

The cylinder @ 135 would cause me concern. Then I would look at the 145 cylinder. From a link I read, 148-152 is the range.

Those numbers are NOT a point of concern as far as the blow by symptoms.

 

[Fireman431]

Re: Help!! More engine problems!!!!

Limited Time,
I'm not sure why a cylinder with low compression with blow-by wouldn't bother you, but it leave me cause for concern.

 

[Coors]

Re: Help!! More engine problems!!!!

Evidently, he has never been 10 miles out, and have this problem.
Never been broke down in 12 foot waves.

 

[JustJason]

Re: Help!! More engine problems!!!!

i don't think 135 as a low with 150 as a high is anything to be concerned about..... but if it makes you feel better do a leakdown test.

its normal to get a little smoke out of the breather tubes... but nothing crazy. What brand and weight oil are you running? and when was the last time it was changed?
Oil out of the dipstick is as don says.... your generating pressure faster than the crankcase and vent it.

 

[Coors]

Re: Help!! More engine problems!!!!

yeah, some serious crank pressure happening, need more info.

 

[thumpar]

Re: Help!! More engine problems!!!!

Limited Time,
I'm not sure why a cylinder with low compression with blow-by wouldn't bother you, but it leave me cause for concern.

If you reread he was referring to the blowby symptoms and not overall engine reliability.

 

[Coors]

Re: Help!! More engine problems!!!!

If you reread he was referring to the blowby symptoms and not overall engine reliability.

???