Survey - Engine issues Merc 7.4L - Should I be concerned?

[BOHM]

I am purchasing a 1996 28ft with a Merc 7.4L and a Merc BravoIII. The survey went well for the hull etc, however the Engine has a few issues that could pose a concern. Interested in your thoughts....

Compression (Cold Test - Could not run engines) 120-130-140

PVC Valve is severed and the lower piece missing, upper piece stuffed in hole, Oil residue on top of valve cover (see picture)

Oil Absorb in bilge (see picture)

Oil level down by a quart

There is no hour meter on the boat.

Thanks!

 

[Don S]

Re: Survey - Engine issues Merc 7.4L - Should I be concerned?

Personally, I would put much faith in the compression test on an engine that has been setting for any length of time (all winter). It needs to be run before it will be meaningful. I have checked them after setting all winter and had low results, ran for 3-4 minutes and rechecked and all was fine.

The oil sorb in the bilge is clean, do you see any indication of oil in the bilge that would indicate a leak? Assuming the boat is out of the water, is it level of the engine slightly bow high? That can effect the oil level.

Broken PCV valve........ replace it.

 

[BOHM]

Re: Survey - Engine issues Merc 7.4L - Should I be concerned?

Don,

Thanks for your input. I agree that warming the engine is ideal, just was not allowed until it is outside. As for the level, it seemed so. I have a photo that leads me to believe it is. The owner has an oil changes scheduled for the spring.

I've attached the photo of the block level.

I see no oil in the bilge, was concerned it could have been cleaned. However it seems he traditional did the service in the spring.

 

[Don S]

Re: Survey - Engine issues Merc 7.4L - Should I be concerned?

I wouldn't get upset about the oil level at this point, and I'm not concerned if the boat is level or not, it's the engine that matters. It may have always been low.
If the owner is going to have the oil changed later, You might want to get an oil analisis done, at your expense of course.

 

[BOHM]

Re: Survey - Engine issues Merc 7.4L - Should I be concerned?

Thanks again. Of interest could be the the outdrive showed a 1/4 past full. Does that correlate?

 

[HT32BSX115]

Re: Survey - Engine issues Merc 7.4L - Should I be concerned?

Thanks again. Of interest could be the the outdrive showed a 1/4 past full. Does that correlate?

That's pretty much as meaningless as the engine oil level. Some oil should be drained from the drive to inspect for metal, water, etc.

That might be a pretty good engine and drive.

I would want to run it under load.

 

[BOHM]

Re: Survey - Engine issues Merc 7.4L - Should I be concerned?

I spoke to the mechanic that works on the boat and got the service history run down. I will be doing a sea trial before accepting the final delivery.

The mechanic believes that the compression will come up 30# once it is warmed up.

 

[Don S]

Re: Survey - Engine issues Merc 7.4L - Should I be concerned?

Normal compression on that engine is 150 psi, I would expect them to even out more, but still be in the 135 to 150 range.

 

[BOHM]

Re: Survey - Engine issues Merc 7.4L - Should I be concerned?

I don't know that increased compression is nearly as imporant as having a consistant reading across all cylinders is.

I agree. I had the surveyor do the engine compression test, not because I don't know how, but because I have a low quality compression tester. Little did I know that he would show up with a compression tester from walmart.

One cylinder showed 150#, but I had him retest it and it was 130#. So you get the idea. I am fairly confident that it will level out with a run and a real tester.

 

[26aftcab454]

Re: Survey - Engine issues Merc 7.4L - Should I be concerned?

I have an 1996 7.4/BravoIII in the 1984 26ft Wellcraft (in avatar )890hours
I have owned it 2 1/2 years and love it .
boat runs 43mph wfo 4600rpm and seems happiest crusing 35OO rpm 30mph- I do not run wfo for a more than few minutes every once and a while.
my boat is very heavy 5700lbs + gen set-& hotwater tank.water & head tanks

I have had minor issues-fuel pump- distrutor cap-plug & wires- normal drive pm service. when I bought it the compresion was all in the 135-145psi range.

The exhaust manifolds & other things will need to be replaced someday but overall I like it!

i hope it checks out to your satisfaction