LA Camshaft plate

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Timmy's Toy

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I am looking to clear up some misconceptions about the front cam plate on LA engines. Actually I don't think they're any different on Magnum's as well. On the oil galleys behind the cam plate is a freeze plug. I have heard that you should drill a very small hole in each plug to let oil out for the chain and you should drill a 3/8 hole in the plate to let this oil out through to the chain via the small hole you drilled. My machinist says to leave the plugs out completely and just butt the cam plate up and everything will be okay. I am having real concerns with that. What is the proper procedure here?
 
You're about to get a variety of responses.
I never heard of what you are talking about ( drilling), but apparently some engines have those little plugs behind the cam plate, some don't.
From what I gather, cam plates are surface ground on the backside on the ones without plugs, but may not be on the ones with.
What was drilled on some engines was one of the bolts securing the cam plate, to piss oil from the valley onto the chain.
 
I have torn down literally over a thousand engines since I've worked on cars. I have seen it both ways. With freeze plugs and without. I don't think it matters. My 331 Hemi had similar holes by the cam plate. They were open when I tore it down. I put freeze plugs in them. I ain't losin any sleep.
 
I find it very difficult to believe that the cam drive would be oil starved if there was NO oil provisions "up there" just from what slops up into the front of the pan during normal running
 
71beater said:
You're about to get a variety of responses.
I never heard of what you are talking about ( drilling), but apparently some engines have those little plugs behind the cam plate, some don't.
From what I gather, cam plates are surface ground on the backside on the ones without plugs, but may not be on the ones with.
What was drilled on some engines was one of the bolts securing the cam plate, to piss oil from the valley onto the chain.
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This is pretty much right. Early engines, 64 through the early 70's, did not have plugs and used the machined thrust plate. Somewhere along the line they started using plugs in the oil galleries. There have been a number of ways to oil the chain, including nothing. 340's and early HP 360's used the drilled through bolt as stated above. I've checked 340 chains on 100,000 mile engines that were raced on weekends and the chains were still in factory spec. Then there was an angled sheet metal guide, and then the chain tensioner. I mostly worked on early engines. I don't think I'd drill the plugs, since I want as much oil pressure going to the rods and mains as possible. I don't see a problem putting plugs in early engines as Rusty said, But I don't do it. If you do use the plugs make sure the plugs don't restrict any of the intersecting lines coming or going from the galleries.
 
I drilled the cam retaining bolt out in my 331. I also put the Mopar timing chain tensioner on it as well. Only minor mods required and it's a bolt on swap. Long as the oil pan has oil in it, the timing chain is GONNA get lubed regardless. Drilling the bolt or leaving one out is only gonna give it a little more which won't hurt a thing. I had to put plug in the holes on the Hemi because of the timing chain tensioner mod. The tensioner doubles as the cam thrust plate. It is a little differently shaped than the original Hemi plate and leaves those holes in the front exposed just a little, so I put some plugs in them. With the drilled bolt plus oil in the pan, I ain't worried about the chain getting oil. It's gonna get drowned.
 
Timmy's Toy said:
I am looking to clear up some misconceptions about the front cam plate on LA engines. Actually I don't think they're any different on Magnum's as well. On the oil galleys behind the cam plate is a freeze plug. I have heard that you should drill a very small hole in each plug to let oil out for the chain and you should drill a 3/8 hole in the plate to let this oil out through to the chain via the small hole you drilled. My machinist says to leave the plugs out completely and just butt the cam plate up and everything will be okay. I am having real concerns with that. What is the proper procedure here?
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Magnums are slightly different. All magnums came with a timing chain tensioner. It replaced the thrust plate. Like Rusty I have seen engines built with and without the galley plugs. Yrs ago I had a 360 that had low oil pressure after a rebuild and I pulled it apart and found the galley plugs missing. Thinking that may be the problem I installed them and it made absolutely no difference.

The last 2 engines I built I drilled a 1/16" hole in the galley plugs and timing chain tensioner to squirt a little more oil on the timing chain cause the cams were pretty big and required high spring pressure. With the SB Mopar chain being so long it's more prone to stretching and I figured the extra oil should help combat the extra force on it with the stout springs and radical cam
 
You can be the exception to the rule, and you never know with Mother Mopar. Seems like we've had this discussion before. Your's is the only early mopar I've heard of, that came with them. And I've rebuilt too many to count.
 
fishy68 said:
Magnums are slightly different. All magnums came with a timing chain tensioner. It replaced the thrust plate. Like Rusty I have seen engines built with and without the galley plugs. Yrs ago I had a 360 that had low oil pressure after a rebuild and I pulled it apart and found the galley plugs missing. Thinking that may be the problem I installed them and it made absolutely no difference.

The last 2 engines I built I drilled a 1/16" hole in the galley plugs and timing chain tensioner to squirt a little more oil on the timing chain cause the cams were pretty big and required high spring pressure. With the SB Mopar chain being so long it's more prone to stretching and I figured the extra oil should help combat the extra force on it with the stout springs and radical cam
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Would it be normal procedure on a magnum engine to install a typical thrust plate in place of the tensioner if someone would have to change the timing set? I have only torn 3 magnums apart, one of them was a "remanufactured by chrysler" 5.2 with a tag riveted to the back of the block. None of them had tensioners, just normal chains and thrust plates. Although, they were all 96-97 build dates. Also, they had plugs.
 
66fs said:
You can be the exception to the rule, and you never know with Mother Mopar. Seems like we've had this discussion before. Your's is the only early mopar I've heard of, that came with them. And I've rebuilt too many to count.
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I doubt I'm the exception. I seem to remember, during that other discussion, that some people's engines had them and some didn't. A few local-to-me guys were the same...some did, some didn't. I wish I'd have taken a pic when I was tearing down the 273 to show them installed. I bought from the original owner, and he says the engine was never apart. :dontknow:
 
I can only go on my experience and what I know. When I was younger, I would tell you that you were mistaken. I have never seen an early small block with plugs in the lifter galleries. It really does not matter, like Rusty said " I put freeze plugs in them. I ain't losin any sleep." You are entitled to your opinion. I have mine, and it will not change.
 
66fs said:
I can only go on my experience and what I know. When I was younger, I would tell you that you were mistaken. I have never seen an early small block with plugs in the lifter galleries. It really does not matter, like Rusty said " I put freeze plugs in them. I ain't losin any sleep." You are entitled to your opinion. I have mine, and it will not change.
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"I'm mistaken'?...You're telling me I saw cam plugs where there weren't any???...Gee, that's rather presumptuous of you, don't you think? I guess you're "The Cam Plug Expert" now? Just because you didn't see it, it didn't happen? I'm not here to change your opinion...frankly, I couldn't care less about your opinion...I'm just telling you what I saw in MY engine. I don't care if you've done a thousand engines.

I sure get tired of people telling me what I did or didn't see with my own eyes, or, in the case of the air shock "discussion", what my butt did or didn't feel!.
 
Cam plug expert. You gotta love it. lol
 
metallidart said:
Would it be normal procedure on a magnum engine to install a typical thrust plate in place of the tensioner if someone would have to change the timing set? I have only torn 3 magnums apart, one of them was a "remanufactured by chrysler" 5.2 with a tag riveted to the back of the block. None of them had tensioners, just normal chains and thrust plates. Although, they were all 96-97 build dates. Also, they had plugs.
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Possibly. Tensioners do wear out and it's quite possible people have replaced them with a thrust plate. I actually haven't torn apart any Magnum's, just base my statements off of so-called experts (Rick Erenberg and several guys on Moparts) statements claiming that all magnums used the thrust plate. Have seen a few pics of them showing the tensioner too. Maybe I shouldn't be a parrot and go by personal findings only. :eek:ops:
 
Actually, when I looked up one for my application, (2000 5.9 Magnum) Cloyes (o.e supplier) ,only lists the Magnum 3.9 v6 coming with it O.E..The tear down for a cam swap,not a tensioner in sight.
 
Abodybomber said:
Actually, when I looked up one for my application, (2000 5.9 Magnum) Cloyes (o.e supplier) ,only lists the Magnum 3.9 v6 coming with it O.E..The tear down for a cam swap,not a tensioner in sight.
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Isn't that interesting! Hard to understand the reasoning for using one on a 3.9 and not a V8, but that's ma Mopar. Wish I had a buddy in a Mopar dealership that I could look it up there to see what it shows
 
fishy68 said:
Isn't that interesting! Hard to understand the reasoning for using one on a 3.9 and not a V8, but that's ma Mopar. Wish I had a buddy in a Mopar dealership that I could look it up there to see what it shows
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ehhhhh......I have seen some 5.2 mags come with them from the factory.
 
65Val said:
"I'm mistaken'?...You're telling me I saw cam plugs where there weren't any???...Gee, that's rather presumptuous of you, don't you think? I guess you're "The Cam Plug Expert" now? Just because you didn't see it, it didn't happen? I'm not here to change your opinion...frankly, I couldn't care less about your opinion...I'm just telling you what I saw in MY engine. I don't care if you've done a thousand engines.

I sure get tired of people telling me what I did or didn't see with my own eyes, or, in the case of the air shock "discussion", what my butt did or didn't feel!.
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I'm sure your engine had lifter gallery plugs. I'm skeptical that it had never been apart. Do I think it is impossible that they were original? No, I think anything is possible with Ma Mopar. Since I knew you would have to continue this ridiculous discussion, I looked in the newest Chrysler parts book I had, 1974, and there are no lifter gallery plugs shown or listed. Carry On
 
I bought a 1992 Dakota in December of 91. It had the 3.9 V6 and I wen't thru 5 timing chain sets. They only lasted about 4000 miles and they started making noise. The dealer mechanic told me it was the engine harmonics of the V6 eating the chains, the V8's were different and didn't have that problem. After the fourth time I called Chrysler's complaint office and I was told that a fix was coming. The fifth time it wen't bad they installed the chain tensioner and it was fine for the next 75,000 miles.
 
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