Too much compression?

[Jimkimmi70]

Re: Too much compression?

Will do this weekend. Seems easy enough.

 

[Lager]

Re: Too much compression?

The 3.0 engine has a vent on top of the valve cover which is attached to the air cleaner/flash arrestor. Any pressure inside the engine should be vented directly in the intake tract and not blow out the dip stick tube.
Unless its a catastrophic piston failure and the pressure is just too much to be vented normally.
Then we have the noise the OP heard.
No offense Mod Achris, But I think the OP needs to maybe have a second opinion from another repair facility, maybe one that will explain things a little more in detail.
I just dont want him to waste his time performing a compression test, when he is not going to understand the readings anyways.
JimKim, what happened to your engine was bad news.When ever an engine blows all the oil out, something really bad happened. You might not need a new engine. I would get a second opinion .
Just like in the Automotive world,
technicians replace components,mechanics repair things.

 

[Jimkimmi70]

Re: Too much compression?

A lot of information on here. All you are awesome for helping. Now that I have the boat back at home I will see what I can find out I am gonna check everything and know more before putting trust in anyone else. If it's a new motor I need than that's what I'll do but I can assure I will know there is no fixing this one first. I will be sure to get someone else to check it out as well. I'll let you all know what I find out. Again thanks for all the help thus far.

 

[Bt Doctur]

Re: Too much compression?

as far as checking ,do a compression test first and post the numbers. finding a very low or zero cylinder could mean it has a hole in the piston. A test to confirm this is to use the comp testing fitting connected to a air source. Hearing or feeling air at the dipstick would
confirm the damage.

 

[aerobat]

Re: Too much compression?

No he said compression but he may have meant pressure. He said the pressure was so high it would push your hand off the oil fill tube. So he may have meant pressure

yes - he meant pressure. you seem to have severe blow-by , when this happened suddenly with a strange noise you might have dropped a valve and holed a piston. in this case your mechanic is unforutnetly right and you indeed need a new engine.

 

[Jimkimmi70]

Re: Too much compression?

You are correct. After further contact and correcting him he said he meant pressure. That being said, running the boat wot at 6000 rpm the engine sounds fine and maintains oil pressure of about 40 on the gauge. No weird sounds and no other issues. I ran it this way for about 15 minutes with the muffs on of coarse.

 

[dubs283]

Re: Too much compression?

running the boat wot at 6000 rpm the engine sounds fine and maintains oil pressure of about 40 on the gauge. No weird sounds and no other issues. I ran it this way for about 15 minutes with the muffs on of coarse.

if you are really running your engine for 15 minutes at 6000 rpm on muffs its no wonder you have issues

 

[Jimkimmi70]

Re: Too much compression?

Sorry I meant I ran it for 15 minutes with muffs on and then put it up to 6000 rpm to listen for knocks or rattles it was only at 6000 rpm for a minute or less. Typing on an iPhone makes it hard to see if you are saying what you mean. Ran at idle to get it to operating temp then reved it to 6000 rpm. But even at that high speed no knocks or anything. No oil water in the oil and no overheating

 

[dubs283]

Re: Too much compression?

in any case revving the engine to 6000 rpm, even momentarily is not good - it is only designed to be ran 4200-4400 rpm wot under load

 

[Bt Doctur]

Re: Too much compression?

posts 26 and 28 mean absolutely nothing , running no load at those settings means you wiped out the impeller in the drive.
If in the water with a prop that small that could give you 6000rpm youd be going 5 mph. Guess you don't know that a 4 cylinder will do that on 3 cylinders no load. What were the compression readings.??????????????????????????????????????

 

[Jimkimmi70]

Re: Too much compression?

Well I won't be doing that again. Went to read the specs. And the rpm limits you said are correct. Luckily I didn't screw the engine up more than it already is. Anyhow, like I said if I had holed a piston or dropped a rod I would hear it. Is it possible that my oil supply was interrupted and as the pressure built it dislodged and blew out all my oil?

 

[dubs283]

Re: Too much compression?

if I had holed a piston or dropped a rod I would hear it

broken rod would make noise at idle and you would not want to run the engine, zero compression on one cylinder may not be so noticable and as bt doc says even on 3 cyls the engine will rev to 6k with no load

did you do a compression test??

 

[Jimkimmi70]

Re: Too much compression?

Compression readings were 155 155 140 150. They may be off slightly but the readings were consistent all 3 times I ran it. One issue for sure is either a bad head gasket or manifold. I have seen water running down the side of the block from the top. And as far as the high pressure the mechanic was talking about I haven't checked it other than to hold my hand over the fill tube like he said he did. It spits a few specs out and I can feel it about an inch up but my truck does that

 

[Jimkimmi70]

Re: Too much compression?

Just to let you all know I will be having a professional repair done on the motor. I am not a mechanic but I am also not a moron. I want as much information as I can get so that some jerk off don't try to tell me things that aren't true. If I need a motor than so be it but if it can be saved then why throw out the money.

 

[dubs283]

Re: Too much compression?

you should lake test the engine, running it with a load may provide different results and pinpoint the issue

 

[Jimkimmi70]

Re: Too much compression?

That is planned for tomorrow. I was gonna run it for a bit and see what happens. After all if I'd listened to him my motor was shot anyway. Lol maybe I'll get one more ride out of it.

 

[Jimkimmi70]

Re: Too much compression?

And on another note. When operating on the water all year last year and two times this year I was at about 4400 rpm going down the river at about 38 mph. I have a 19 pitch and that is the recommended pitch for skiing according to the mercruiser dealer in Jackson. Don't know if he is right but the boat did great that way

 

[Lager]

Re: Too much compression?

Wish you the best Jimkin.

 

[achris]

Re: Too much compression?

And on another note. When operating on the water all year last year and two times this year I was at about 4400 rpm going down the river at about 38 mph. I have a 19 pitch and that is the recommended pitch for skiing according to the mercruiser dealer in Jackson. Don't know if he is right but the boat did great that way

Those numbers look good in my prop calculator...

Your compression numbers also look good.

Revving to 6000 on muffs, even for a few SECONDS, is not a wise thing. The owners manual says not to run the engine above idle on muffs, and there are reasons for that. Best abide by that in future.

I'd take a timing light to the engine and check the timing. If it's too far advanced, that could account for the strange noises...

Chris......

 

[MikDee]

Re: Too much compression?

Running any engine to yellow, or redline, with NO LOAD on it, is a path to Destruction! The rings burn out due to overspeed, if the crank bearings don't seize first, due to sudden instant stress, & not enough oil there initially to handle it. This actually takes a toll on your whole engine, it figures don't it?

So, please no over revving in neutral, "Just to see what the engine can do?" This is not really a test, it's more like playing "Russian Roulette!" especially without being in the water, even the muffs can't handle much more then a fast idle.