Hey guys...Hope everyone had a good holiday. I have a question. Please excuse my ignorance....I'm not an engine guy. This is a motor that was built aprox 3 years ago by an engine builder. It's a 54 331 Hemi. Its been sitting while I'm working on my frame, cab & bed. In working on clocking my oil pump shaft, I needed to bring my #1 Cly up to TDC on compression. In doing so I noticed that I didn't seem to have any sort of compression pressure. I have not primed the motor by drill running the oil pump yet, I'm waiting for the shaft to arrive from HH. The compression I'm seeing by turning the crank slowly with a breaker bar is 12 psi. Firstly.....Have I done any damage by turning the motor by hand without priming? I've probally turned the crank 10 or less revolutions. Hopefully I have not done any damage. I'm going to check my rocker adjustments.... I have the stanke roller rocker train. Maybe the valves are not fully closing. Can anyone answer my question.... and give me some direction? Thanks much
I believe you'll never crank it by hand fast enough to get a proper compression reading. It's not totally sealed so will leak down probably as quickly as you can hand crank it. There should be more than enough oil in the assembly procedure to prevent any damage so far, but you need to get the oil primed. Also good to turn the engine over in storage particularly if the valves are adjusted up. Chris
^^^^ what he said. Prime the oil pump, drop in the distributor, and check the compression using the starter.
If you have the valve cover off, then you can se if the valves are open or shut. Pull the spark plug and watch the piston rise. Once it's at the top, you got TDC.
There are two tdc in every cycle so make sure its the correct one. Watch the intake open as the piston is going down and then as the piston is coming up both valves will be closed and that will be the correct tdc for your distributor to be pointing at #1 firing.
You haven't harmed anything by rotating the assembly, in fact when my freshly rebuilt engines are sitting during body and paint I turn them occasionally by hand, so they aren't sitting in the same spot all the time. I don't know if it is necessary, but I saw it done at a hot rod shop once and I adopted the practice.
You haven't done any harm to your engine. I'm impressed that you got 12 psi with a breaker bar in an engine that hasn't been run. I agree with the advice given above. I squirt a little rem gun oil in cylinders that haven't been run in a while and won't be for a while. Avoid wd40. just my .o2 and worth about that.
Thanks for all the informative quick answers guys.... So glad to hear I haven't done any damage! Happy New Year!
How can I be sure I'm at the 120 degress past #1 TDC on Comp Stroke? I'm using a balloon, once the ballon fills I'm inserting a soft tipped rod into the cly and continuing to go clock wise until the piston stops coming up. This is at the 20 degree mark on the crank. If I use the hot head tape to measure around +120 degrees it puts me about 10 degrees past the 270 mark. I spun that bugger with the drill for about 2 minutes and no oil at the rockers. How do I get to the right spot? Thanks
Just a question, but why the need to get to 120 degrees? I assume the Hemi is like an L6 where the oil pump is driven off the cam gear? So then you want to orient the position to insert the drive tang on the distributor properly?
He’s wanting to lube the rocker shafts,,,,I don’t know the angle needed for the Chrysler . I know the ones for my Desoto,,,,,,but it’s not at 120 or 270 ,,,lol . Tommy
So if my reply doesn’t pertain, is there a need to clock the oil pump? Again, no answers, only questions edit: I think I get it. Orient the crank to spin the oil pump and the crank is then in the proper position?
Yes...I've been told 120 degrees past TDC on #1. I'm using a timing tape to measure out the 120 but can't seem to find the sweet spot. I'm trying to follow this if you guys can get to FB https://www.facebook.com/profile/100064708779597/search/?q=Priming
Mike,,(Budget36),,,,, I can’t imagine a real need to clock the pump in a Mopar . When inserting the intermediate shaft,,,,,just get it to engage the tang . Then,,,,you can easily rotate it anywhere you desire with a large screwdriver . We just recently performed this on my sons OT truck engine . He was wanting to align the tang on the distributor,,,,and was apprehensive about the intermediate . I said,,,,,,,look at the distributor and see where you need the rotor tip placed . Ok, son ?,,,,,,now look at the intermediate,,,,once you place the intermediate shaft where you want it,,,it can only be in time or 180 out after that . He dropped in the intermediate,,,,it was a few teeth out of position,,,,he was very upset . I laughed and said calm down,,,,,,he took a big screwdriver and turned the shaft right where he needed,,,,,he didn’t realize how easy it was . It amazed me how quick it fired after that',,,,,hit the key,,,,about 2 or 3 turns and it lit,,,,what a thrill ! Lol . Tommy
Apparently there is a specific position required on the crank to line up the oil holes which send the oil up to the rockers. A different specific location for each bank. If you can watch mark spencer in the facebook video above it explains it. It's not like you can see the holes line up....you have to go by the 120 degrees past TDC and I'm taping it but not luck on oil flow to the rockesrs
I get ya for sure now. I’d bet that all engines are the same way, but seems one person has taken it to perfection. I’ve always just spun the pump to get pressure, rotate the engine a bit, spin the pump, just kept doing that. But I’m not trying to advise you, and it seems the fellow may have it set up and figures it out where things need to be. And thanks for the clarification
Cool beans 36.... Mark says that not doing it is the #1 cause for galling in the rocker train. It makes sens me to me. I'm gona get back at it tomorrow and will keep you guys posted.
Hey Coop , That’s a beautiful engine there man . Any luck in finding the oiling hole angle ? I don’t know the Chrysler angle,,,,but my DeSoto is different I’m sure . On mine,,,,,the drivers side is approximately 170 degrees,,,,or almost exactly BDC on #1 fire . The right side is approximately 550 degrees (360 + 190) on the dampener,,,,,or almost exactly BDC on #6 fire . That’s my DeSoto,,,,,and I’m certain that is simply a ballpark degree setting . I modified my oiling holes a little,,,,,,and it also depends where the factory drilled the passages . I’m interested about your experience though,,,,I read where the engine was built 3 years ago by a professional engine man . I hope it was a Mopar engine man,,,,,,,all engines are not created equal . When I went through mine not long ago,,,,I installed my cam bearings,,,,always do . As many sets as I have done,,,I assumed they were aligned correctly,,,,,they seemed to be . A I was putting in the crank and cam , I noticed the oiling holes were way off . #2-#4 cam bearings were not in line correctly . I noticed the holes from the manufacturer were extremely small,,,,,but I assumed they were at least in the right spot . One side had a very small orifice alignment,,,,the other side had nothing . I redrilled the holes,,,,,,removed the cam bearings,,,,,dressed and deburred the bearings . Cleaned all the passages again,,,,,,then finally got my bearings back in and everything fit perfectly . After putting in the crank,,,,,I was lubing the oil journals,,,,squirting oil in the holes and spinning the crank . Oil was running out of the deck holes facing down,,,,,dripping on the floor ! My point is,,,,if those holes line up,,,,,oil will come out freely while turning the oil pump and rotating the crank . Good luck man ! Tommy
Have you got an oil pressure gauge connected up so you can confirm you’ve got oil pressure? Did you notice a change in resistance when spinning the oil pump? Looking at an oil feed diagram your Hemi feeds oil from the 2 and 4 cam journals. It’ll only feed at a specific point in the cam rotation when the hole in the cam line up with the port to the head. See photo below. If you can’t find the exact crank position that works then once you know you’ve got oil pressure get someone to turn the crank slowly whilst you operate the drill. You’ll need two whole crank rotations to get one cam rotation. Just noticed Tommy explained all that above.
Thanks Tommy! I haven't gone back at it today. If I can't find that spot where the holes line up... I'll need another set of hands to slowly turn the crank as Oneball said. Yes....I do have a oil pressure gage and am reading 60 psi. The oil filled my filter and I can see oil moving in the galley and around the pump shaft bushing I also have an email in to Mark but prob won't hear back until Tuesday. Did you guys get to watch Marks Facebook video? I'll keep you guys posted. I'm chasing other things today. Thanks for your help.....much appreciated.
If you want to accurately find TDC, you need to make/buy a "piston stop". www.amazon.com/ZFLXH-Universal-Piston-Stroke-Engines/dp/B09336RX24/ref=sr_1_1_sspa?crid=3M2OZMTYUI8YX&keywords=piston+stop+tool&qid=1703977742&sprefix=piston+stop%2Caps%2C105&sr=8-1-spons&sp_csd=d2lkZ2V0TmFtZT1zcF9hdGY&psc=1 Be sure it is for your size spark plug hole. Rotate your engine till it touches the stop. Make a reference mark on the harmonic balancer or the flywheel. Rotate the engine in the opposite direction till it touches the stop. Make another mark. Halfway between the marks is your TDC for what ever cylinder you are using.
Doesn't matter where the piston stop, it will always be the same spot no matter which way the crank turns. One thing about turning the engine multiple times, if it has a flat tappet camshaft, you have already wiped off all the break-in grease if any was installed. If it had camshaft lube on it when installed, it's all in the oil pan now, so the only lube on the lifter and cam surfaces is residual oil left behind. If you have a roller cam, you still need to get it primed as soon as possible or quit turning it over. Its much better for the engine to back off the rockers then to keep turning it over. If you want to oil it, plug all the open holes, add your oil, the flip the whole engine over and let the oil coat the insides.
That gets you half way there. You have to know whether you are on the compression stroke or the exhaust stroke.
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