340 oil galley plugs

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LJ67barracuda340

LJ67barracuda340

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I'm looking for verification on an oil plug problem. My brand new 340 build destroyed the main bearings in 6 hours running. Found metal on the magnetic pan plug. Changed the oil 4 times thinking the machine shop didn't clean the block and it was flushing but the metal kept coming. I know I should have torn it down on the first inspection so you don't need to bring that up, lol.
The crank should clean up at .010". Back to the plug issue. When I got it out of the shop the first time I noticed the two drive in plugs under the cam plate were missing and the two allen plugs at the back of the oil galleys were out too. Spoke to the shop and they couldn't understand why they were still out. I installed those but didn't notice the plug wasn't in the back of the block near the oil filter and during priming pumped 4 quarts of oil into the bell housing and had to have the clutch refaced. Now at the second trip to the shop they asked if I removed the plug that would be under the oil filter or the 90* adapter. Told them that I didn't remove any except water plugs. So the question is, is there supposed to be a plug under the filter (the hole is threaded) I can't remember seeing one or not? Do you think having that one missing would effect the main oiling? Looks like it goes to the lifter galley. They are blaming over fueling so getting fuel in the oil. I have a FITech system that was still learning. I'm thinking trash left in the block from boring and honing or having to crank it a lot at first start because of a ignition issue. They are being helpful on parts cost and doing the block work free, (feeling guilty maybe). Just don't need the cost of another tear-down. By the way when it started cold the pressure was 75#, idled hot at 35# on 10 w 30.
Larry

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There are a few more....
1. One at the back of the driver's side lifter gallery just in front of the distributor shaft. This one being missing drops overall oil pressure a bunch.
2. One or 2 in the block right above where the oil pump outlet hole goes up throuhg the #5 main bearing cap and up into the block; this one forces the oil to go over into the filter. Without it, the filter is bypassed but it does not lower oil pressure. The anti-drain-back feature of the oil filter is defeated if this plug is missing and each startup has delayed oil pressure build-up.

FYI, the oil after the filter goes up into the passenger side lifter gallery; that is the main supply line to all the mains, rods, cam, and rockers. It then passes across the #1 main bearing (where those 3 small holes come together above the #1 main bearing shell in the main saddle) and then feed into the driver's side lifter gallery.

What was the oil pressure while all of this was going on? Please specify hot or cold, oil weight, and if running at 2000RPM or higher, or at idle.
 
And excess cranking and bad FI tuning could overfuel the cylinders and put gas in the oil. How were the cylinder bores and pistons at treardown? It would be circumstantial evidence but bore damage has a fairly high probability of showing clear evidence of overfueling the cylinders, especially after 6 hours.

And I hate to tell you this, but the cam may now be suspect; long non-running cranking at start up can ruin a cam lobe and/or lifter. What cam?
 
I had a problem with oil pressure on a new build and it turned out that the **** shop took out the oil plug behind the distributor as previously mentioned and didn't put it back, it took me forever to figure it out since I went through all the obvious ones. I suggest you take the time to pull out the distributor and intermediate shaft, you'll know right away by feeling if it's there or not. I didn't recall but what was the oil pressure? Mine was 8 at idle but the drivers side lifers wouldn't fill up. Best of luck.

Jaje
 
xLURKxDOGx said:
I had a problem with oil pressure on a new build and it turned out that the **** shop took out the oil plug behind the distributor as previously mentioned and didn't put it back, it took me forever to figure it out since I went through all the obvious ones. I suggest you take the time to pull out the distributor and intermediate shaft, you'll know right away by feeling if it's there or not. I didn't recall but what was the oil pressure? Mine was 8 at idle but the drivers side lifers wouldn't fill up. Best of luck.

Jaje
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Who assembled the engine? That's who is responsible for plugs missing.

I would call a shop a **** shop if they DIDNT take that plug out.
 
Take this plug out. There should be another smaller plug farther up in that hole that threads into the back of the left side lifter oil galley. If the shop left that plug out, I'll bet that's your problem. The only way I know to get to it is remove that plug I circled. You will need a long allen wrench to insert it through that hole and thread it into the block.

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With that plug behind the distributer possibly being out/missing would he still have 75# start up oil pressure and 35# idle warm oil pressure? Just curious myself
 
yellow rose said:
Who assembled the engine? That's who is responsible for plugs missing.

I would call a shop a **** shop if they DIDNT take that plug out.
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That's fine if they did it, but don't tell me you did not do it when I called them and asked specifically about what plugs they pull out, or at very least tell them when they picked the engine up that the plugs were missing and needed to be installed. I had 3 engines at that same shop and this is the first time it happened, maybe they did their job right this time.

Jake
 
NM9,,,, the cam is a Hughes hyd roller and it seems to be fine with a buff on the main journals. The bores still had the cross hatch and the rings never seated in and were sharp on one edge, the shop said that indicates over fueling and lack of lube.
 
mopardude62 said:
Take this plug out. There should be another smaller plug farther up in that hole that threads into the back of the left side lifter oil galley. If the shop left that plug out, I'll bet that's your problem. The only way I know to get to it is remove that plug I circled. You will need a long allen wrench to insert it through that hole and thread it into the block.

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thanks I'll look for that.. did not know that was there.
 
LJ67barracuda340 said:
thanks I'll look for that.. did not know that was there.
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And you can see that 2nd plug (the one in FRONT of the distributor shaft) with a mirror through the distributor hole. Yeah, that is a BIG one to leave out... you have a 'hole' in the oil delivery system!

OK on the hyd roller cam; you may be perfectly safe with that being the case. Examine the lobes and rollers before putting back in. I'd look for any signs of heated metal or scraping marks or anything like that.

Are you gonna replace the rings? I would certainly look hard at doing that. I suspect they will never seat in now; the surfaces may be hardened up. New rings would require a light fresh hone in the bores. No point in messing around on the ring seal, IMHO.
 
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dgully said:
With that plug behind the distributer possibly being out/missing would he still have 75# start up oil pressure and 35# idle warm oil pressure? Just curious myself
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If you mean the one rigtht in FRONT of the distributor shaft (that is in the back end of the driver's side lifter gallery), the answer is no; there have been plenty of such issues that show up here time to time, and the common symptom is markedly low oil pressure, nearing 0 at idle when hot in some reports. That plug is at the far end of the whole oiling system and puts an 'end wall' in the oiling system against which pressure builds.
 
nm9stheham said:
If you mean the one rigtht in FRONT of the distributor shaft (that is in the back end of the driver's side lifter gallery), the answer is no; there have been plenty of such issues that show up here time to time, and the common symptom is markedly low oil pressure, nearing 0 at idle when hot in some reports. That plug is at the far end of the whole oiling system and puts an 'end wall' in the oiling system against which pressure builds.
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That's what I was thinking too
 
Yes I'm using new set of rings with a light bore hone and unfortunately a new set of Hughes retro lifters$. I suspect the trash is in the lifters and I can't take them apart to clean because the piston below the snap ring wont come out past the tie bar rivet. If I get the rivet out I'm not confident it'll stay in on reassembly.


OK on the hyd roller cam; you may be perfectly safe with that being the case. Examine the lobes and rollers before putting back in. I'd look for any signs of heated metal or scraping marks or anything like that.

Are you gonna replace the rings? I would certainly look hard at doing that. I suspect they will never seat in now; the surfaces may be hardened up. New rings would require a light fresh hone in the bores. No point in messing around on the ring seal, IMHO.[/QUOTE]
 
There's a plug that gets missed. It was mention above, it will show oil pressure,but won't send any to the filter. Search online to get the measurement you remove the oil pressure sensor and slide a thin rod in and how far it goes in tells you if the plugs there. Can't remember the distance. See in the picture the two horizontal bosses. It goes between them in a passage 90 dregs to those bosses

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Don't forget the plugs on each end of each rocker shaft. I'd inspect the rockers and bottoms of the shafts, too. Don't ask me how I know. Let's just say that 5yr/50k mile warranty wasn't worth anything when you're dealing with poorly trained service mechanics.
 
this is the plug I'm concerned with. they say it was out so they had to have been the ones who removed it and didn't reinstall. I've been studying it and I think i'd still have pressure but the oil would be returning to the filter and not enough going to the mains.

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rustycowll69 said:
Don't forget the plugs on each end of each rocker shaft. I'd inspect the rockers and bottoms of the shafts, too. Don't ask me how I know. Let's just say that 5yr/50k mile warranty wasn't worth anything when you're dealing with poorly trained service mechanics.
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one of the first things I checked after I found metal.
 
LJ67barracuda340 said:
this is the plug I'm concerned with. they say it was out so they had to have been the ones who removed it and didn't reinstall. I've been studying it and I think i'd still have pressure but the oil would be returning to the filter and not enough going to the mains.

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You are correct in that if you leave out the plug you have circled in the picture, it will not filter all the oil.

That is another plug I always remove. The only one I don't take out is the soft plug under the main cap. Every other plug should come out. If you don't put them back in its a problem.

The very first 318 I built was in 1980. I paid a guy to clean and prep the block and I checked all the clearances and put it together. Went to prime it, and the main oil gallery on the passenger side didn't have the plug installed. I didn't catch it and I primed 4 quarts of oil right on the floor. I was pissed, but it was my fault because I didn't verify all the plugs were in.

I can only think of one other time in 37 years I missed a plug. It was a jap engine and I just missed it. Fortunately, I primed it and found the issue before the customer got it.
 
yellow rose said:
You are correct in that if you leave out the plug you have circled in the picture, it will not filter all the oil.

That is another plug I always remove. The only one I don't take out is the soft plug under the main cap. Every other plug should come out. If you don't put them back in its a problem.

The very first 318 I built was in 1980. I paid a guy to clean and prep the block and I checked all the clearances and put it together. Went to prime it, and the main oil gallery on the passenger side didn't have the plug installed. I didn't catch it and I primed 4 quarts of oil right on the floor. I was pissed, but it was my fault because I didn't verify all the plugs were in.

I can only think of one other time in 37 years I missed a plug. It was a jap engine and I just missed it. Fortunately, I primed it and found the issue before the customer got it.
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thanks,,,and trust me I wont miss a plug again.
 
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