This engine needed a complete rebuild because the rear piston completely failed, leaving metal all through it and the rear rod bearing was out, I have no idea which came first. I separated the case and cleaned every port in everything, including support plate. I left the oil cooler off because I was afraid I couldn't get it clean enough. The engine fired right up but after running awhile it developed what I figured to be valve train noise. I have a new oil pump and new lifters and have checked everything and when I get the Baisley spring in I am going to do as suggested and put a gauge on it. The crank I put in had less that 20k and rods and wrist pin bushings were as tight and smooth as could be. It runs so nice that if I can get the oil to the top cured I should be fine. Time is limited but when I get it going again I will report on the results. Thanks folks.
top end oiling
- Thread starter corrigon
- Start date
dolt
Well-Known Member
How long have you run the motor? Did you prime the lifters before installing? Did you spin the motor a bit via the starter (plugs removed) before firing her up?
Installing the Baisley spring in an early model is not a bad idea; it will help idle and low rpm oil pressures. The oil mist that goes up the pushrod tubes the top end is oiled only by the piddle valves in the lifters and the oil that goes up the center of the pushrods; flow rate is usually about 3 - 5 oz. per minute. Any signs of oiling? Look for oil pooled by the exhaust valve. If it has been oiling at all there should be some evidence of it. It'll make a bit of a mess, but with the motor running and the cover off you should see the oil slinging off of the rocker tip if it's oiling. As long as the lifters are getting oil and the piddle valves are working the oil should be getting there.
Open up the pushrod tubes; if oil is getting to the lifters, oil is moving throught the cam plate as it should. Installing the Baisley spring, as previously mentioned, is not a bad idea but if oil is getting to the lifters, it is just a matter of time before it gets up top.
More questions on this oil pressure problem. With a gauge after running just long enough to let engine warm a little I can get about 30 lbs at 2000rpm. Idles at about 7-8 As it warms a little more the pressure fluctuates and starts coming down. My question this time is I removed cam chest cover and started engine. It will dump what I guess would be a quart of oil in about 8 seconds. I never let it run over 3-4 seconds because of the amount of oil coming out. It has new oil pump with new o rings. Is this normal to have that much oil in the cam chest?
dolt
Well-Known Member
Your oil pressure is normal; no issues. Don't worry about oil in the cam chest; there will always be oil there.
Have you checked for any evidence of oiling up top as suggested? Check for oil pooling around the exhaust valve spring seats. Have you checked the pushrods for obstructions. I always check pushrods for obstructions before installing and, every now and then, I find something.
Correct me if i'm wrong but what Dolt says is a good suggestion as far as small amount of ounces flowing to the rocker boxes and the twin cam doesn't oil the top end as much as the older evo and shovel. I thought this was by design to keep oil temps down during design of the TC motor.
I did check the tubes before installation and they are open. I just got it buttoned up again today and I will check for top end oiling after a test run. I read the same thing about top end oiling on tc engines Big Al, supposed to make oil run cooler. I just want to see some up there.
BUBBIE
Well-Known Member
IF and I say "IF" you get some pieces of small metal in the lifters from the junk that was in the motor and MISSED.....
The lifter is a good Oil Filter,,,, metal pieces in but NEVER out. Not saying it IS the problem but SURE could be...
A small piece of something in the lifter... Could be the lifter noise you talked about.
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How long has the motor run and you say not enough oil in the top end...
Minutes, hours, days???
The piddle valve should allow oil into the upper area and YES it does take a little time to get there.
One good hour ride out and oil should be totally there.:dknow
signed....BUBBIE
The lifter is a good Oil Filter,,,, metal pieces in but NEVER out. Not saying it IS the problem but SURE could be...
A small piece of something in the lifter... Could be the lifter noise you talked about.
***************************************
How long has the motor run and you say not enough oil in the top end...
Minutes, hours, days???
The piddle valve should allow oil into the upper area and YES it does take a little time to get there.
One good hour ride out and oil should be totally there.:dknow
signed....BUBBIE