Yes another IMS question

[rossignolskibum]

I have a 98 boxster and the center bolt for the IMS broke. What are the chances the motor is junk???? Is there any way to check if the piston and valves touched with out tearing apart the engine???? Will a leakdown test be proof???

[ltusler]

Pull the plugs and see if you can manually turn it over. Get a bore scope and look at the top of the pistons.

[rossignolskibum]

motor is out of the car and it will turn over manually, not that that really means anything...what gets me is that the timing is still in line....really confused, guess a scope is the only way...

[LanceGT4]

How about pulling the flywheel and rear seal and checking for slack in the timing chains?
if a valve is broken or bent wouldn't that stop it from turning over?
Good luck to you

[txhokie4life]

Originally Posted by LanceGT4

How about pulling the flywheel and rear seal and checking for slack in the timing chains?
if a valve is broken or bent wouldn't that stop it from turning over?
Good luck to you

Put a boroscope down the spark plug holes -- look for valve strikes.

Many times a bent valve is cleared by the piston and no longer interferes if
otherwise in time.

Pull the oil scavenge pump covers and check that the camshafts are indeed in proper time.

It is possible that despite the loss of the bolt -- the tube still spins fine and
has remained in time.

If that is the case -- buy a lotto ticket to pay for your IMS retrofit -- which will be harder due to not having a bolt to yank on -- but there are bearing pullers that you
can use -- or you can *gasp* -- cut it out.

Mike

[rossignolskibum]

Thank you all for the info...I found a great deal on a rehab motor that I could not pass up..however does anyone have any tidbits on what I should look for when purchasing a used motor...SO far I have been told the following:

-Obviously check the IMS

-Remove the water pump to see if there are any broken fins as this is the root cause of blocks cracking

-Replace the AOS before install

Any further help would be appreciated....

[Sapientoni]

If the timing set tool can be properly inserted, there's a great chance there is nothing damaged inside the motor. If you are going to put the rehab motor in, I'd be 100% certain the IMS bearing is new. Many mechanics without proper training can hammer a new bearing into anything. It is IMPERATIVE the proper tools and techniques be used or damage to the new bearings will be done and the life will be greatly shortened. If you can get each cylinder to TDC and apply air pressure to a leak down tester, with the crankshaft securely blocked, there will be almost no loss of air unless a valve is bent. If the pressure drops almost immediately to zero, there's a bent valve.

Best of luck.