Cambelt Tensioner Rebuild - Piston Size

[pmth95]

Car is 105H, engine is from 261H.

Ordered a rebuild kit for my Automatic Tensioner. The Nylatron Piston in the kit is both larger and longer than the original metal piston. The only reference on the tensioner is A907E1141.

Are there different versions of the tensioner?

[mike.griese]

I have never seen a metal piston in one of these tensioners, but then I have only worked with Federal wet sump 910 engines.  From the parts manuals, there are two different part numbers for different engine and accessory combination.  The difference is between AC and non-AC cars for 912 engines and wet sump and dry sump 910 engines.  Regardless of the tensioner assembly part number, they all used the same nylatron piston part number.  So I guess I don't know what you have there.

[pmth95]

According to post #3 in this thread on LotusTalk, the metal piston would indicate a very early tensioner. 

In addition to having the metal piston my tensioner had a rubber cap over the piston.

Might have to consider making a Nylatron piston, or sourcing a later type assembly. 
 

 

 

[drdoom]

Can't be right with bushes absent.

[pmth95]

5 hours ago, drdoom said:

Can't be right with bushes absent.

Yes, it was time for a rebuild. Wonder how those bushes disappeared...

[ekwan]

You could get someone to machine out some phosphor-bronze bushings.

 

[mike.griese]

That link to the article on LotusTalk indicates that the early automatic tensioners didn't have bushes on the pivots, so this one is consistent with that comment.  You might be better off looking for a later tensioner.

[jtmco]

I had forgotten but I believe when I bought a new piston, the diameter was a bit larger. I had a machine shop enlarge the hole. 

[pmth95]

Got a new metal piston of the correct early size from PNM. Will consider replacing it with Nylatron in the future. Tensioner ready to go back in the car 

[GavinT]

I recall 165H had the metal piston tensioner when I first acquired the car eons ago. I ordered the tensioner rebuild kit from SJ’s and the piston did not fit. At that time that there wasn’t an original sized piston available. Luckily a complete tensioner assembly was posted on eBay in the US, I bid on it and won. Paid about $15 IIRC. Used the rebuild kit to build the eBay tensioner and installed it. The original is in a box on the shelf.