cam thrust plate

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siuauto

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hello everyone. I want to start out by saying how great of a website this is. I have yet another question regarding my 360 (my first small block) I have the engine out and I am taking it apart and I noticed the cam thrust plate has four bolts in it. I have a 340 sitting next to it and it has three bolts and a pointer on it. Now I know the pointer is to lube the chain. My question is three part. Why would it have all four and doesnt the bottom right hole (as you are looking at the front of the engine) lube the chain. If it does should I replace the chain. It is a double roller and I thought I would reuse it since it is already broken in. Also I saw the thrust plate on Summit and in the pic it has four bolts sitting next to it. Last question I promise, how many of you are running a tensioner from a magnum?
 
hello everyone. I want to start out by saying how great of a website this is. I have yet another question regarding my 360 (my first small block) I have the engine out and I am taking it apart and I noticed the cam thrust plate has four bolts in it. I have a 340 sitting next to it and it has three bolts and a pointer on it. Now I know the pointer is to lube the chain. My question is three part. Why would it have all four and doesnt the bottom right hole (as you are looking at the front of the engine) lube the chain. If it does should I replace the chain. It is a double roller and I thought I would reuse it since it is already broken in. Also I saw the thrust plate on Summit and in the pic it has four bolts sitting next to it. Last question I promise, how many of you are running a tensioner from a magnum?

I'm running the mag tentioner and it works grate!
It's on a 340 and the passenger side, top bolt, has a hole drilled thru it.
oil from the cam valley(?) flows oil threw it and on to the chain.

If you left that bolt out you would just get more oil.
 
There are several options for the plate(s), special holes with bolt holes for oil dripping, a tang tab and a plate with holes and no holes, and a groved plate for drip as well. Here are some pics to add to your questions, good luck!

Thrust Plate OILER BOLT (this special bolt is thru-drilled for oil passage; its one of the four bolts that mount the thrust plate to the block; the other three bolts are standard bolts)

thrust plates.jpg
 
I'm running the mag tentioner and it works grate!
It's on a 340 and the passenger side, top bolt, has a hole drilled thru it.
oil from the cam valley(?) flows oil threw it and on to the chain.

If you left that bolt out you would just get more oil.

If you are running the tensioner does that use all four bolts, and does the new tensioner come with new bolts.
 
Ok so I just looked at my thrust plate and it has a groove on the back side. Does this mean I use all four bolts?
 
Ok so I just looked at my thrust plate and it has a groove on the back side. Does this mean I use all four bolts?


It has been a while sense i installed my Timing Chain Tensioner but you will have to drill the 4 hole to us it with the new tensioner.

I didn't,............Timing was way easier to see at 2500 rpm after the tentioner was installed.

The tentioner replaces the thrust plate...........
 
the Cloyes tensioner uses 3 bolts as it was made for the 3 bolt magnum block, and the old LA bolt with a hole in it drains standing oil from the lifter valley, not the pressurized lifter oil galley as its in the wrong position. The plate shown on the bottom has a galley relief that will leak oil out the pressurized lifter galley onto the timing chain area if its mounted cast areas to rear.
 
Regardless of the oiling at the top, some oil will dribbel out from the front edge of the #1 main bearing and work its way onto the crank sprocket and into the chain.

FWIW, tensioner parts wear on the rubbing blocks and can't go forever, and the rubbing block material can also get brittle and break up over a very long time. (Maybe 10-15+ years?) That's the main reason we did not put one in my son's 340.

OP, how many miles on the existing chain? If you put it on, and push the chain on the passenger side so all the slack is there, how much left-to-right movement can you get, in fractions of an inch?
 
hello everyone. I want to start out by saying how great of a website this is. I have yet another question regarding my 360 (my first small block) I have the engine out and I am taking it apart and I noticed the cam thrust plate has four bolts in it. I have a 340 sitting next to it and it has three bolts and a pointer on it. Now I know the pointer is to lube the chain. My question is three part. Why would it have all four and doesnt the bottom right hole (as you are looking at the front of the engine) lube the chain. If it does should I replace the chain. It is a double roller and I thought I would reuse it since it is already broken in. Also I saw the thrust plate on Summit and in the pic it has four bolts sitting next to it. Last question I promise, how many of you are running a tensioner from a magnum?

Read this thread for how to assemble the front of a small block:

How to Assemble the Front of a Small Block
 
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