'87 944S Rod Knock
05-08-2012, 10:31 PM
#1
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Location: Vermont
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'87 944S Rod Knock
Hi All,
I recently acquired a 944S in rough shape and started working on it in a effort to get it running right. So far, I've replaced the cam chain and tensioner, timing and balance belts and rollers, front seals, water pump, head gasket and lifters. After all this it still runs like crap.
The compression was down on #2 when I checked it initially. Prior to pulling the head, I hooked an air hose to a fitting and blew some air in the spark plug hole, and air came out of the intake, so I assumed I had a bent valve. It was actually just a valve that needed to be lapped. While the head was off, I didn't notice any scoring on the cylinder walls. I put it back together with new lifters since the old ones were all collapsed. The problem is still there.
I am now pretty sure that the #2 rod bearings are toasted, and I'm trying to determine the best course of action.
What are the chances I can get away with just replacing the bearings? Should I go through the effort of dropping the oil pan, or just throw in the towel at this point and part it out? Can the S head and belt rollers be swapped over to a non-s motor if I find one?
Any ideas?
Thanks,
Mike in VT
I recently acquired a 944S in rough shape and started working on it in a effort to get it running right. So far, I've replaced the cam chain and tensioner, timing and balance belts and rollers, front seals, water pump, head gasket and lifters. After all this it still runs like crap.
The compression was down on #2 when I checked it initially. Prior to pulling the head, I hooked an air hose to a fitting and blew some air in the spark plug hole, and air came out of the intake, so I assumed I had a bent valve. It was actually just a valve that needed to be lapped. While the head was off, I didn't notice any scoring on the cylinder walls. I put it back together with new lifters since the old ones were all collapsed. The problem is still there.
I am now pretty sure that the #2 rod bearings are toasted, and I'm trying to determine the best course of action.
What are the chances I can get away with just replacing the bearings? Should I go through the effort of dropping the oil pan, or just throw in the towel at this point and part it out? Can the S head and belt rollers be swapped over to a non-s motor if I find one?
Any ideas?
Thanks,
Mike in VT
05-09-2012, 10:51 AM
#3
Administrator - "Tyson"
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I've seen the aftermath of a 944 rod knock that had no damage to the crank or connecting rod.
Plan on replacing the oil cooler too and giving the enigne a good flushing, bearing debris will be everywhere. I know some techs that always tear down a head in the event of a rod bearing failure.
Yes
Blocks & cranks are the same
05-09-2012, 11:36 AM
#4
50/50
I've seen the aftermath of a 944 rod knock that had no damage to the crank or connecting rod.
Plan on replacing the oil cooler too and giving the enigne a good flushing, bearing debris will be everywhere. I know some techs that always tear down a head in the event of a rod bearing failure.
Yes
Blocks & cranks are the same
I've seen the aftermath of a 944 rod knock that had no damage to the crank or connecting rod.
Plan on replacing the oil cooler too and giving the enigne a good flushing, bearing debris will be everywhere. I know some techs that always tear down a head in the event of a rod bearing failure.
Yes
Blocks & cranks are the same