175hp cylinder walls and absurd compression results

pastorbud

Chief Petty Officer
Joined
Jun 1, 2005
Messages
555
and it may run....Deo Volente. Recommend reading or rereading Zen and the Art of Motorcycle Maintenance -- probably a sermon or two in there, with illustrations from your outboard experience :).

Well, I got the new head gaskets on.

I borrowed a SnapOn compression tester from my Ford mechanic friend. I finally got a stable, trustworthy compression reading.

the first two cylinders both measured 50 psi. That was with a cold engine, but I don’t think it warning it up will bring it up to spec from that far down.

Looks like ol girl needs a rebuild.

This was a project motor for a project boat. I have two other project motors, so on to my next victim!

it’s a 1998 150, (J150EXECD), which had compression problems (ironically). I did not want to bother with it, because it has plastic carburetor bowls that are leaking (warped) and I was afraid of the fancy electronic ignition condition system. But it’s worth a second look.

I will one day get this powerhead off the 1982 I have been working on, and send the block out for a machine shop to look at it. But for now it will sit in the backyard while I work on the other motors.

I’ll start a separate thread on the 1998. I’m new to Johnson/Evinrudes so I know I’ll have questions. Thanks for the help. I learned a lot, even though it didn’t turn out to be repairable for now.
 

oldboat1

Fleet Admiral
Joined
Apr 3, 2002
Messages
9,598
Didn't you have a Chrysler or Force that might have some promise? If you go that route, wouldn't mind a heads-up here, and will find you on the other forum. It's been a long time since I tinkered with a big Chrysler, and would like to follow along -- even if your Force is more Merc than Chrysler.

Thanks.
 

pastorbud

Chief Petty Officer
Joined
Jun 1, 2005
Messages
555
Didn't you have a Chrysler or Force that might have some promise? If you go that route, wouldn't mind a heads-up here, and will find you on the other forum. It's been a long time since I tinkered with a big Chrysler, and would like to follow along -- even if your Force is more Merc than Chrysler.

Thanks.

You got a good memory! Yes, I have a Force 150 in the garage. I have the power head on the midsection, but no lower unit on it. I have the lower unit, but it needs a carrier bearing (which I have in ANOTHER Force lower unit—-Lord, I’m a hoarder!)

Boat came with an Evinrude 150 looper. Switching to the Force is a little tricky. I have controls and cables for the Force, but I’m not sure about the steering— the boat has hydraulic steering and I think I’d need some kind of adapter to connect to the Force.

The Evinrude is the engine that came with the boat, so I know the steering will work.

i just hate those plastic carb bowls.

I will one day complete that Force 150. I hear they were pretty good motors....impressive power/weight ratios. And all-metal carbs that are easy to get to!
 

oldboat1

Fleet Admiral
Joined
Apr 3, 2002
Messages
9,598
Yup. Future projects. Thanks for the comeback -- will be on the lookout.
 
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