Author Topic: Rebuilt engine break in  (Read 1399 times)

Michael Foster

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Rebuilt engine break in
« on: August 31, 2022, 23:15:15 »
Well I am soon to be ready to start my rebuilt engine from MM. My rebuilt transmission from sun valley is on the way.

I want to bench test to be sure that everything is good. I have read much on this subject and want to be sure I do it right. I understand that I should turn over the engine without plugs to get the oil pressure up (with regular non synthetic oil), then fill with water and prime the fuel lines (maybe the water and fuel could be done before), get the oil pressure up aging and start it up. run for about 30 seconds, shut down and check for leaks. Start up again and run at varying RPM up to around 1500 to 2000 for about 20 minutes (checking for good oil pressure, water temp and exhaust gas temp) and stop and retorque the head and adjust the valves.

Should this be good to install the engine in the car or should I run it a little more before installing in the car?


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Re: Rebuilt engine break in
« Reply #1 on: September 02, 2022, 17:39:49 »
It's an engine coming from Metric Motors.  IMO, install it, and start it/break it in, based on Mike's recommendations.  I've built a lot of engines, I've never "bench tested" any of them.  Depending on what Mike and crew did to your engine, it may not need the camshaft break-in procedure, which is to start the engine and bring it immediately to 2000rpm, and leave it there for 20min, with no idling time until after that 20min.  And yes, cranking the engine over with no load on the crankshaft (spark plugs removed) in 15 second bursts, until oil pressure is confirmed, is correct.


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Re: Rebuilt engine break in
« Reply #2 on: September 02, 2022, 19:58:52 »
i had a full Metric Motors long block re build.
i just followed their instructions,  if i recall correctly keep the rpms down and change the oil after 500 miles or so. 
Austin Tx
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