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Author Topic:   pulling/servicing motors
posted September 04, 2003 05:20 PM
Kind of a newbie question but, how often during the season will a typical guy running say a hobby stock, mod, or a sprint car end up pulling apart his motor-for example, pulling the motor from the car or the heads or the cam?
Is it like some seasons, the motor is apart everyother race chasing problems and some seasons it never comes out? Or do most guys check them every few races regardless?

posted September 04, 2003 07:39 PM
i run in a bomber class and i took my motor out once last year because my oil pump pick up tube fell off other wise i would have left it on all year 20 nites on a motor is what i run then i re ring and bearing it

posted September 04, 2003 08:28 PM
mke sure you cutyour oil filter apart every time you change oil! if you find alot of copper and such in it the motor needs to come out

posted September 04, 2003 08:39 PM
In our mod we will go through our primary motor ea winter and then run it all season, or about 25 races. I know some guys that run em till they break, which could be 10 races or 40 races. Personally we have never had to tear one apart in the middle of the season for any reason. On the other hand outlaw sprint cars may go through them every 3 or 4 races, but they get abused a little more too. I guess a lot of it is how well they are built, how hard they are run and how well you take care of them, barring any major problems of course.

posted September 05, 2003 01:31 PM
Pure stock motors running between 6000-6500 and I inspect ours every winter. The one motor had a bad gas/detonation problem that caused a mid year tear down and 1 new piston & ring pack. The rod bearings and cam were spotless, so they were reused. The mains were worn a bit and were replaced. That was after about 12 races and it has 20-25 races on it since. I did replace the cam, lifters and timing chain at the end of last year.

Monitoring oil pressure, oil consumption, blowby and doing compression/leakdown tests is my way of knowing when it will be time for a complete rebuild. So far, oil pressure has remained constant and compression tests have dropped less than 5 psi (still all over 180psi) since it was new. During the year, I try not to tear into it unless something breaks or tests show it's checked out. With a set of bearings being $100, rings another $80-$100 and gaskets $100 it's a little expensive to re-ring 'just because'.

posted September 06, 2003 08:15 AM
I run about 20races tear down in the winter.Inspect all parts with a fine tooth comb.Don't fix what a'int broke during the season.Keep clean oil in it ,check your filter every week,and do'nt run it hot. If you put it together right it should last a season with no problems

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