Engine building woes
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Teching In
Joined: Jan 2012
Posts: 43
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From: Morgantown Ky
Engine building woes Here's a rundown of the engine. SBE lq4 new king bearings throughout, new total seal rings, btr cam and 243 heads.
Started the engine on a stand this weekend. There was a large vacuum leak so on the first 6 or 7 starts the engine ran at high rpms. Fixed the vacuum leak and the engine ran at about 1200 rpms. The rings would not seat so I decided to tear it down to hone the cylinders. I found the rod bearings to be trashed, the crank to be grooved and the main bearings to be trashed. The coating has come off of the bearings. Any ideas as to what happened here?
Started the engine on a stand this weekend. There was a large vacuum leak so on the first 6 or 7 starts the engine ran at high rpms. Fixed the vacuum leak and the engine ran at about 1200 rpms. The rings would not seat so I decided to tear it down to hone the cylinders. I found the rod bearings to be trashed, the crank to be grooved and the main bearings to be trashed. The coating has come off of the bearings. Any ideas as to what happened here?
Use Total Seal Quick Seat powder on the cylinders during assembly to help the rings seat
The factory rods just do not re torque perfectly round
they end up out of round by as much as .0012" which effectively murders your bearing clearances and prematurely trashes the new bearings
The now discontinued Katech bolts minimizes that distortion number to .0003" or less which is why for years guys were able to just R n R them without incedent.
Take your rods to a machine shop to have the big ends re honed, They should clean up and straighten out while still being inside max spec. Next time your bearings will thank you
The factory rods just do not re torque perfectly round
they end up out of round by as much as .0012" which effectively murders your bearing clearances and prematurely trashes the new bearings
The now discontinued Katech bolts minimizes that distortion number to .0003" or less which is why for years guys were able to just R n R them without incedent.
Take your rods to a machine shop to have the big ends re honed, They should clean up and straighten out while still being inside max spec. Next time your bearings will thank you
