I posted a message a couple of weeks ago about my nephew's '87 240 timing belt problem. I had a chance to work on it yesterday. Several teeth were stripped from the belt. When I tried to turn the cam sprocket, it was stuck until I worked at it for a while. I positioned the 3 sprockets, installed the new timing belt, but wouldn't start (seemed like it was firing, but wouldn't start), changed plugs & put timing light on #1 plug wire. Timing light fires, so seems like it's getting spark. Removed and looked at new plugs, they appear moist, so I think they're getting fuel. Checked the oil and found it to be off the dipstick, added 3 quarts and it was still low. Checked the compression and all cylinders were around 30 lb. Added some oil to cylinder #1 and rechecked the compression, it came up to around 40 lb. Is the engine toast? Would the low compression keep it from starting (temp was around 20F)? Is the low compression a result of lubricant depravation? Thanks for your help.

"When I tried to turn the cam sprocket, it was stuck until I worked at it for a while."
Remove the cam cover, see if there is oil getting to the shaft. Spinning the intermediate sprocket. Try turning cam, with socket wrench on sprocket nut watching for binding. (there will be a certain amount of resistance due to spring action.)

"Checked the compression and all cylinders were around 30 lb. "
Make sure cam is positioned right. Ie. if cam is opening valves while pistons are compressing, compression results will be lower.
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1980 245 Canadian B21A with SU carb and M46 trans

If the bearings are scored slightly, as pointed out in the previous posts, you have a lack of oil feed to the head. A new belt won't fix that. The plug in the oil system normally occurs in the head gasket between the oil drilling in the block and the number two exhaust side headbolt. You should remove the head and replace the gasket, and spin the intermediate shaft to confirm oil flow. Then remove the cam, and the plugs on the rifle drilling in the head and confirm they are clear. With a new gasket, the head will then get the oil it needs, and nothing more needs to be done (except change the oil regularly).

Hmm. Very low oil and a very tight camshaft suggest that the cam ran dry of oil and might be binding.

If it were my car, I'd remove the cam cover and then yank bearing cap #2 (#1 is frontmost) and examine it for signs of galling. Then I'd replace it, remove #3, examine; then replace it and pull and examine #4.

If there's even the tiniest suggestion that the cam ran dry, you must deal with that problem first. (It's not life-threatening -- that problem can be fixed in your garage, I've done it very successfully with ordinary hand tools.)

I would also be sure that the alignment pin 'tween cam and sprocket is intact. Sometimes, when the cam bearings bind, the pin will shear. Then, when you install a new belt, the alignment marks on the sprockets will be correct but the cam will still be outta time (and can also wander from there).
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Don Foster (near Cape Cod, MA)

don with all do respect at this point i might be thinking motor change
earthman

Yeah, it might get to that. But it's good to start with the simple (and repairable) stuff before swapping a motor.
--
Don Foster (near Cape Cod, MA)

true but my gu

true but my gut tells me to start looking for a motor

Maybe.... but it's strange that ALL cylinders have compression pressure around 30 psi. Too consistent. Volvo motors don't fail that way without some kind of catastrophic event, such as overheating.
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Don Foster (near Cape Cod, MA)

your right it is weird that they all have the same compression still and all i'd worry about that bottom end

Don is right. This engine is no doubt repairable at far less cost, and less effort, than swapping in another used engine, which may develop exactly the same problem.
It would be like changing engines just because you stripped a spark plug thread.
Fix it, don't change it.

87 small main bearing motor and ran it out of oil
earthman
ps b230f motor can be had for about 2-3 hundred dollars out of a junk yard and are very smiple to change

"When I tried to turn the cam sprocket, it was stuck ..."

That may be why the belt stripped teeth. And the new belt may be stripped also. That would explain the low compression, I think.

Sound like a siezed camshaft bearing or two. It may be fixable with some careful scraping of the cam bearing and journal surfaces. Try the FAQ or Search on Siezed Cam.
--
Bruce Young,
'93 940-NA (current)
'80 GLE V8 (Sold 5/03)
'83 Turbo 245
'76 244 (lasted only 255,000 miles)
73 142 (98K)
'71 144 (track modified--crusher bound)
New 144 from '67 to '78
Used '62 122 from '63 to '67