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1098 Oil Consumption

ABfish

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My 1098 is burning a considerable amount of oil. It barely smokes on startup, but I get a whiff of burning oil when cruising with the top down. I would estimate I'm burning a quart in about 150 miles. Odometer is broken, so I'm guessing at mileage.

Compression test on warm engine shows 170 psi on numbers one through three, and 130 psi on number four cylinder. A shot of oil in number four brought the reading to 200+ psi.

Can one bad cylinder cause this much oil consumption? Is there any solution other than a full rebuild, or any other type of test that I should do? The 130 psi reading doesn't seem that low to me, but I have no experience with these engines.
 
200? I would guess you put a LOT of oil in it, or your gauge calibration is way off, but that's just a guess.
10% variance is what you look for, or 17 pounds less than the 170, which would be 153 minimum.
Oil bringing up the compression means rings, not valves, so it's time to pull the head and pan, pop #4 out, and be prepared for broken rings and/or trashed piston.
Check the bore carefully for scoring from said broken rings and/or trashed piston.
 
Would be interesting to see how much the other three come up when oiled. Might just be time for a full bore and rebuild.

You might get lucky, and only have worn rings, but it will require a teardown to find out.
Dave
 
I know that you're supposed to put a teaspoon or so of oil in the cylinder. I did a little free-hand pouring through a funnel, and probably put too much in. (I have the same problem when free-pouring gin and tonics).

Can you pull a piston in these cars without removing the engine?
 
Yes and no. You can pull the piston by taking off the sump and unbolting the rods from the crank and pulling the piston up through the top after taking the head off. But you might find out later on that more work is needed, then you will most likely have to take the whole engine out.
 
That's how I used to do overhauls. Yank the head, drop the pan, unbolt the rod and push it up with a hammer handle from underneath.

I had a moron...errr....qualified mechanic work for me for a short pewriod of time, who put like 10 pumps from and oil can into the bores.
You just need enough to temporarily seat the rings...one pump is usually more than enough.
 
I realize that an "in frame" and only pulling out one piston would be the cheap way to go, but I may try it this winter. I hate to put the little guy out of commission during driving season.

I suppose the best outcome would be a broken ring in that cylinder?
 
Yes and no. Yes if the broken ring did not damage the cylinder. No because it usually, or at least quite often, does. Best of luck to you.
 
I meant, and thought I said, for an inspection.
If you do it (early in the non-driving season) and the bore is bad, THEN yank the motor and do the whole thing.
One way or another, you need to pull at least that slug and find out what damage you have.
 
With your 1098 do you have the PCV Valve in place, "Flying Saucer" vented off of the timing chain cover or are you losing out of the back seal. With my 1098 until I got the PCV Valve set up correctly I thought I bought the Exxon Valdez.

Also exhaust pipe and how far it sticks out behind the car can sometimes allow exhaust to be circulated back into the passenger copartment. My wife sometimes complains I smell like car exhaust after driving Bugsy my '68 even with a windblocker in place which dramatically reduced exhaust smell.

I've got a similiar uneven compression level between the cylinders but a Qt of 20W-50 every few tanks of gas for the amount of driving miles I put on Bugsy isn't excessive for an almost 50 y.o. engine with unknown mileage. I think I leak more than I burn. As long as it isn't visible burning blue smoke deal with it afterthe driving season is over.
 
Jim_Gruber said:
With your 1098 do you have the PCV Valve in place, "Flying Saucer" vented off of the timing chain cover or are you losing out of the back seal. With my 1098 until I got the PCV Valve set up correctly I thought I bought the Exxon Valdez.

Also exhaust pipe and how far it sticks out behind the car can sometimes allow exhaust to be circulated back into the passenger copartment. My wife sometimes complains I smell like car exhaust after driving Bugsy my '68 even with a windblocker in place which dramatically reduced exhaust smell.

I've got a similiar uneven compression level between the cylinders but a Qt of 20W-50 every few tanks of gas for the amount of driving miles I put on Bugsy isn't excessive for an almost 50 y.o. engine with unknown mileage. I think I leak more than I burn. As long as it isn't visible burning blue smoke deal with it afterthe driving season is over.

Jim-
I've got the PCV valve in place and it appears to be working correctly. I see very little blue smoke, just a tiny puff upon startup, so the amount of oil consumption has surprised me. I read some of your posts about crankcase pressure and oil leaks


This car is no creampuff, but it has very little oil leakage. In fact, I don't see any oil on the concrete in my shop where the car is normally parked.

I think I'll just keep adding oil until I get the chance to dig further this winter. Right now, the only pressing issue is a rear brake replacement.

I guess the next big decision will be whether to rebuild the 1098 or find a 1275!
 
I've got a spare 1275 in the back of my shop with sames issues, 150, 160 120 110 something like that that I'm told was a real sweet running 1275 out of a '69 that all of a sudden started using oil and the owner got an opportunity to acquire a 1380 and a 5 speed for the right price. I goet a 1275 and a rib case for $250. A good deal and it's been awaiting time and funding to rebuild. I was going to use for Bugsy but will be destined for Bugsy II a 59 BE if I can close the deal. Right now my 1098 runs sweet, pulls strong, starts almost too quickly and will run fine for a long time yet.
 
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