Hey guys, I just started up my 455 that's been rebuilt, and the oil presure is too low. The motor was completly rebuilt by a local builder with all new components installed icluding rebuilt heads. I installed the oil pump and top end.
Whent the engine was completed, I primed the pump with a drill, and the oil guage showed 25 lbs of presure. Asssunimg the low presure was due to the slow speed of the drill, I completed installing the engine and got it runnning.
At idle, the oil guage indicates 5-10 lbs. of presure at idle and 25 lbs when I rev her up to about 2500 rpm. I was thinking that the new oil pump may not have been adjusted properly at the factory and I'll have to pull the enging back out to replace the oil pump. Would you agree? Or is there another answer before I pull the engine?
Good thoughts. I just tried the adapter and it's fine, I'm pretty sure the bearings are in right since it runs well, and isn't hard to turn over. I think I remeber putting the oil pump gasket in.... not sure.
What's an oil galley? Also, can you tell me specifically where they both are? How far should I tear it the engine down to get to therm? Just wondering if I still need to pull the engine to check them.
Hi Jim, yeah I happen to have another one and tried it. same results. I'm thinking that becasue I did'nt see any oil to the rockers even when I reved it, then the gauge is probably pretty close.
I second the oil galley plug theory. There are actually three. Two in the front behind the timing cover. If one or both, or all three are missing, you won't get oil to the rockers. The two behind the timing cover are just drive fit and staked in. The third one you are able to see if you remove the distributor and use a small mirrior in the hole. It is a threaded plug. If it's not there the motor's got to come out. Access if through a freeze plug in the rear of the block.
I just had my engine rebuilt by somebody last year and they forgot to install the rear galley screw in plug. I had no oil pressure in the pax side rockers. I had oil psi in the rest of the motor. To remedy this problem I did not have to pull the motor. I had to pull the tranny and remove the small pax side freeze plug(non threaded) to get to the threaded plug which could be seen with a mirror if the dist was pulled or can be felt with a finger if you know where to feel. Be very careful not to drop the plug into the motor. After replacing it everything was normal. Two machine shops said everything would probably be ok in the motor if it wasn't driven too much because that aft plug is at the end of the oil routing except to the pax rocker arms.
I pulled the distributor on the 455, and with a mirror in the distributor hole, I saw a about 3/4 inch or so plug installed. Is that the one your referring to?
Also, I have a 350 on my engine stand with the timing cover off and could see 2 small 1/2 inch plugs behind the timing chain. Are those the front ones your referring to?
If so, then it sounds like I'll pull the timing cover off the 455 and see if the 1/2 inch plugs are istalled.
Those be the ones. If all the plugs are present you may have an oil pump issue which will require pulling the pan/engine. I'm in the process of doing that exact thing right now(well, in a few minutes). There was something stuck in the pressure bypass of the oil pump. Not a common problem, but it happens. Mostly when using a new pump that has not been opened and checked out before being installed.
You guys were right. The two front oil galley plugs were not installed. I put them in, threw it back together, and tested it with the drill and got 60 lbs of pressure. Thanks for the advice. Now if I can only get the distributor to seat all the way in I'll be running agian. I pulled the distributor to test the pressure with the drill and when I went to re-install it, it won't seat all the way in. I tried lining up the oil pump shaft with the distributor, but it still does'nt seem to go in all the way. It could be that I was working on it at 1:00 am..... I'll try again during the day time.
You're going to have to mess with it a bit to get it back in. You'll have to turn it a bit at a time with a screwdriver till you get it lined up. Might take a couple of tries.
Thanks, yeah I got it in. I made sure things were lined up and tried again. I actually had it in the right posiiotn, just had to push down and wiggle the distributor more than I did the other night. The new enigine runs great.
