Timing Chain Tensioner Extended too much?

[Ownallday]

I just did a rebuild on a L28 engine however I stupidly did not order a new timing chain or tensioner so I reused my old ones. Engine is already placed back into the vehicle but before turning keys just want others opinion on if this tensioner being extended this much is acceptable for a first start and break in? The chain has good tension and somewhat acceptable slack. Rotated the engine multiple times too didn't see signs of it being a problem at least by hand. Any insight would be appreciated.

[heyitsrama]

>Engine is already placed back into the vehicle but before turning keys...

 

did you assemble the whole thing and reinstall it? or is the front cover off?

In this image below from "How to modify your nissan/datsun OHC engine" the head of the tensioner looks like it is close to the guide.

 

[heyitsrama]

It looks like you can adjust which position the sprocket is in in order to adjust the tension on the sprocket.

EDIT* DON'T LISTEN TO ME, IM WRONG HERE SEE

Edited November 13, 2023 by heyitsrama
i cant read correctly

[Ownallday]

13 minutes ago, heyitsrama said:

>Engine is already placed back into the vehicle but before turning keys...

 

did you assemble the whole thing and reinstall it? or is the front cover off?

In this image below from "How to modify your nissan/datsun OHC engine" the head of the tensioner looks like it is close to the guide.

 

Yeah the entire engine is put back together including the cover. Car is at my friend's house and he is in a rush to get it out of there but after comparing pictures the tensioner looks alarming. I remember trying to see if I was able to extend it more by hand and checking to make sure it would stay put and it seemed like it wasn't going anywhere. My cam sprocket is placed at #1. Should I adjust it to 3 or would that be difficult with the timing cover on?

[heyitsrama]

Shoot back to your buddies place and to the test that is shown in EM-52, when I was rebuilding my motor the new chain was so tight it only fit on notch 1.

I think you can adjust the sprocket with the cover on, people swap cams with the engine inside... just don't let that chain drop.

 

EDIT: See

 

Edited November 13, 2023 by heyitsrama

[Ownallday]

6 minutes ago, heyitsrama said:

Shoot back to your buddies place and to the test that is shown in EM-52, when I was rebuilding my motor the new chain was so tight it only fit on notch 1.

I think you can adjust the sprocket with the cover on, people swap cams with the engine inside... just don't let that chain drop.

Will do, most likely will be able to do Sunday or Monday with him that's when we planned to start it. I remember the chain not being tight for me when it came to installing the cam sprocket. I have a new chain on order but I typically get that stuff in two weeks and he needs the car gone by Wednesday.

[heyitsrama]

Ahhh.. well if sprocket 3 is still too far out what do you plan to do? run it as is?

There are plenty of Z shops in So-Cal, MSA is down there too, I'm sure they can get you a chain set, AutoZone says they can get me one by 11/13.

Edited November 13, 2023 by heyitsrama
i'm wrong

[Ownallday]

1 minute ago, heyitsrama said:

Ahhh.. well if sprocket 3 is still too far out what do you plan to do? run it as is?

There are plenty of Z shops in So-Cal, MSA is down there too, I'm sure they can get you a chain set, AutoZone says they can get me one by 11/13.

Run as is and just hope it doesn't pop out I suppose. When comparing with a picture of another tensioner completely out, it looks like mine still has about 4mm-6mm before that shaft comes out completely. I'd basically just drive the car back to my house (60 miles away from his house) and wait to install the new one chain before driving regularly. I ordered from Zcardepot. Didn't think to check AutoZone to be honest. MSA was pricer and still usually takes an entire week or two to get unless I pay for the faster shipping obviously but shipping is already expensive as is.

[heyitsrama]

I RockAutoed all my stuff. Z Car Depot is an option...

Amazon is not bad either. (order in 43 min and get it Sunday for me)

https://www.amazon.com/Cloyes-9-4134SA-Multi-Piece-Timing-Kit/dp/B000C08IM0/ref=sr_1_1?crid=3FKC99YRVAE1M&keywords=94134SA&qid=1699683391&sprefix=94134sa%2Caps%2C121&sr=8-1&ufe=app_do%3Aamzn1.fos.006c50ae-5d4c-4777-9bc0-4513d670b6bc

[Ownallday]

37 minutes ago, heyitsrama said:

I RockAutoed all my stuff. Z Car Depot is an option...

Amazon is not bad either. (order in 43 min and get it Sunday for me)

https://www.amazon.com/Cloyes-9-4134SA-Multi-Piece-Timing-Kit/dp/B000C08IM0/ref=sr_1_1?crid=3FKC99YRVAE1M&keywords=94134SA&qid=1699683391&sprefix=94134sa%2Caps%2C121&sr=8-1&ufe=app_do%3Aamzn1.fos.006c50ae-5d4c-4777-9bc0-4513d670b6bc

Oh wow, didn't even think to check Amazon either. I only ordered the chain though as the other websites only have everything as a set. I have spare gaskets and had new guides on hand so I didn't need the kit.

[grannyknot]

Don't start that engine, that tensioner piston is extended way too much, when the timing cover is installed the rubber block on the tensioner piston should be up against receiving block just like in the photo that heyitsrama posted.

If that piston pops all the way out, the chain will bunch up and there will be many bent valves.  You need a new chain and tensioner.

[Captain Obvious]

Couple comments...

As Granny suggested above, that tensioner is sticking out too far. I would not start the engine like that.

8 hours ago, heyitsrama said:

It looks like you can adjust which position the sprocket is in in order to adjust the tension on the sprocket.

About the three holes on the upper timing gear...  those holes do not adjust the tension on the chain. They affect the cam timing with the respect to the crank location, but don't have any effect at all on chain tension. Moving from one hole to another won't do anything to fix this problem.