No oil in pass. head?

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Sounds like the cam bearings are not clocked right. Long story short, I sent my 340 out to be checked by a local machine shop and had them throw in new cam bearings and core plugs. I go to put the engine together a year later and realized the idiot had the cam bearings in wrong. He nearly had all the oil feed holes completely blocked off. So what I did was drill through the cam bearings to make a complete opening and counter sunk the holes slightly to remove any burrs.
 
71Scamper said:
Sounds like the cam bearings are not clocked right. Long story short, I sent my 340 out to be checked by a local machine shop and had them throw in new cam bearings and core plugs. I go to put the engine together a year later and realized the idiot had the cam bearings in wrong. He nearly had all the oil feed holes completely blocked off. So what I did was drill through the cam bearings to make a complete opening and counter sunk the holes slightly to remove any burrs.
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I always use a wire coat hanger and probe the oil holes before assembling anything into the block. Straighten the hanger, and then poke it down the oil holes and look through the cam tunnel to make sure that it goes through.

Also do this with the main bearing holes in the block.

Make sure that the passages are clear and nothing is obstructing them. It's more difficult to check like this now after it is together.

It is good that you were able to fix yours, but it is risky to do that way. You have to make sure that you remove any burrs/chips or they can cause problems.

The best way is to replace the bearings with new ones and make sure that they are lined up properly with the oil feed holes. You should not push them out and re-use them, as they will not have the same retention force the second time and you risk spinning a cam bearing. The rule of thumb is the holes cannot be more than half blocked or they have to be redone. I would want more personally, but 50% overlap is the maximum.
 
krazykuda said:
I always use a wire coat hanger and probe the oil holes before assembling anything into the block. Straighten the hanger, and then poke it down the oil holes and look through the cam tunnel to make sure that it goes through.

Also do this with the main bearing holes in the block.

Make sure that the passages are clear and nothing is obstructing them. It's more difficult to check like this now after it is together.

It is good that you were able to fix yours, but it is risky to do that way. You have to make sure that you remove any burrs/chips or they can cause problems.

The best way is to replace the bearings with new ones and make sure that they are lined up properly with the oil feed holes. You should not push them out and re-use them, as they will not have the same retention force the second time and you risk spinning a cam bearing. The rule of thumb is the holes cannot be more than half blocked or they have to be redone. I would want more personally, but 50% overlap is the maximum.
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I washed the entire block out after this with hot soapy water then re-coat with fresh engine oil to keep it from rusting til I got it completely together. The only reason I opted to drill the hole instead of replacing was, A: I wanted a full passage to the bearings instead of a partial opening, and B: I really didn't want to replace the bearings again.
 
71Scamper said:
I washed the entire block out after this with hot soapy water then re-coat with fresh engine oil to keep it from rusting til I got it completely together. The only reason I opted to drill the hole instead of replacing was, A: I wanted a full passage to the bearings instead of a partial opening, and B: I really didn't want to replace the bearings again.
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I understand.

Not everybody could do it right like you did.
 
Alright, So I got the passenger side rocker shaft off.

O95zKWj.jpg


It looks like oil is getting up there. Maybe just not very much? Low oil pressure maybe?

I figure next thing to do is to check the rocker shaft for obstructions? I don't know how it could be obstructed, but it's the top of the system and I guess I can just work my way down?

Thanks a tonne for all the help so far. :)
 
Awful dry in there. Big picture looks like nothing getting there to me. Did any pressure show on your gauge?
 
Daves69 said:
Awful dry in there. Big picture looks like nothing getting there to me. Did any pressure show on your gauge?
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I've only got the stock idiot light.

There is a little oil pooled at the back of the head and some in the oil passage deally as well as the rear-most rocker-shaft bolt hole. And there was a little oil on the two rear most rockers.

I guess "a little bit of oil" doesn't really count for much, huh?
 
have someone crank it over with the rocker arm shaft off and check oil flow out the oil feed hole in rocker shaft stand. I've never built a magnum eng ,do the headgaskets interchange where the oil passage hole is cut? if no oil can the problem be wrong headgasket without oil holes,???
 
teringer said:
have someone crank it over with the rocker arm shaft off and check oil flow out the oil feed hole in rocker shaft stand. I've never built a magnum eng ,do the headgaskets interchange where the oil passage hole is cut? if no oil can the problem be wrong headgasket without oil holes,???
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All gaskets wether magnum or LA have the holes in the gaskets for oiling the rockers.

The magnum Non LA blocks don't have the oil provision to oil the rockers to go LA.
 
If I understand thing correctly, the rockers for cylinders 2, 4, & 6 are not getting oil. Oil to the passenger side rocker arm shaft comes from the second rocker arm shaft bolt from the firewall. Since the engine normally sits in a nose-up attitude, it makes sense that if a reduced amount of oil is available, it would puddle near the #8 cylinder. The rocker arm shaft acts as a manifold to distribute oil to the rockers.

Suggest the following diagnostic steps.

  1. Using a priming tool, ensure the engine is able to develop proper oil pressure. If oil gallery plugs are missing or mis-installed, look for oil coming out of the bottom of the bell housing or transmission housing if the car is connected to an automatic.
  2. Remove both rocker shafts.
  3. Turn engine over by hand observing oil flow from the second bolt hole from the firewall on the passenger side and and the second hole from the radiator support on the driver side. If oil flow looks equal, the problem is in the passenger side rocker arm shaft. Reinstall driver side shaft. Repair and replace passenger side shaft as required.
  4. If the flow is diminished to the passenger side, the problem is between the cam and the bolt hole. Attempt to clean out the passage. The oil passage approaches the bolt hole at a shallow angle and may be entered if the shaft on a small diameter brush is not too rigid. Turn the engine over by hand occasionally to use oil pressure to flush out the passage.
  5. If flow is not restored (or even if it is, if this engine is going to see a lot of rpms), remove the camshaft. Inspect the next to the last journal so see if there is damage. If so, there is a problem with the block. If not inspect the next to the last cam bearing to see if it is installed correctly and that it is undamaged. Replace damaged items.
Hope this helps. Good luck.
 
Rev If you preoil with it 2&17/32" ATDC #1 compression you might move the crank slightly from that dimention in either direction as your cam timing may be slightly off from what made the oil passages line up for me. FYI the DR side oils 5" (79 deg) BTDC #6 compression. It sounds like the filter was filled & you might take off the mechanical oil psi sender at the top rear of the block & stick a thin copper welding rod down & post what you get for disance to the top of the deck. It's a mini freeze plug so get the rod down all the way in the middle of it. EDIT I would suggest not cranking it as this is a new cam breakin but to turn to the 2 sweet spots & fire up the drill
 
On a small block:
Turn the motor to 90* before top dead center coming up on #1 compression. The pass. side rockers should get oil.
Turn the motor to 20* after top dead center just past #6 compression. The drivers side rockers should get oil.
 
I ain't sure why Tony has different numbers for the sweet spots, the only thing I can think of is that I checked that on a radical circle track cam and I will recheck my mumbers. Rev holler back with any news. I would definitely find the sweet spots for your eng & preoil & see if the horizontle galleries are being fed (lifters did clatter) and that the heads are being oiled.
 
Corrupt_Reverend said:
How long should it take oil to squirt from the feed holes while cranking?
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I would strongly recommend not cranking the engine while trying to figure out this problem. You could really be doing some damage by cranking the engine over before your cam is broken in. Another problem could be the plug that goes in between the two passages in the rear of the block.

look at post #15 for a picture: http://www.forabodiesonly.com/mopar/showthread.php?t=266852
 
Is the oil plug that is under one of the main caps installed? I had to check for it once when my motor was together because I forgot to check initially, thankfully it was there.

To check get a welding rod or a wire thats at least 10 inches long and insert it into the little hole beside the distributor (The oil pressure sending unit hole). If the rod goes down 7.5~7.75 inches I believe it there, and any more its missing.
 
I think that he should put a gauge on it now and find out if he has any pressure in the engine. '

Then we look for an obstructed passage...

I would buy a mechanical gauge and hook it up at least for troubleshooting.
 
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