Tightening timing chain

jsilva

Greenie N00B Member
Greenie Member
I’ve seen some videos of people working on Mazdaspeed engines and they seemed to loosen the end of the exhaust cam in order to make the chain very taught.

Is this normal and expected? Would you do this on a used chain? And would you need to replace the friction washer?

Thanks.
 
I’m putting the engine back together and figured I take the opportunity to make sure the chain is the correct tightness.

This isn’t the video I was thinking but he basically does the same thing (but with both cams).

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Both cam bolts are loose and he tightens them at around 7:45. I’m assuming this was to ensure the chain was tight.

I do happen to have some friction washers for the cams. Does it make sense to loosen the exhaust cam bolt to make sure the chain is tight when I put it back on?
 
there is a tensioner on the system making sure the chain is tight. You shouldnt have to do anything with the cam gears for that. You just need to make sure its all timed correctly and that you have a new (not used) chain on it.
 
https://www.mazdaspeeds.org/index.php?threads/timing-the-mzr-disi.8722/

Both cams bolts will be installed but loose and you will add tension to the chain using the tensioner. This allows the cams to remain in the spot they need to be for timing while also making the chain tight against them. You will then tighten the cams "exhaust side first"

Thanks Johnny :) I have done it once before although I didn’t loosen the cam bolts. I should do it this time and I just happen to have two friction washers.

I see in the other thread it looks like you have a new front oil seal. Do you think it should be replaced each time?
 
If you're taking the front cover off you should replace the front crank seal while you're in there since the crankshaft pulley isnt keyed to the crank and friction washers need replacement.

If you just replaced it then it's up to you. It would be better than having to take it all apart again because it leaked after repairs.
 
If you're taking the front cover off you should replace the front crank seal while you're in there since the crankshaft pulley isnt keyed to the crank and friction washers need replacement.

If you just replaced it then it's up to you. It would be better than having to take it all apart again because it leaked after repairs.

I do have the friction washers. I hadn’t considered replacing the seal though. I guess it’s cheap enough and I’m going to dealership this morning anyway (I’m order some seals for the transfer case which is leaking).
 
I do have the friction washers. I hadn’t considered replacing the seal though. I guess it’s cheap enough and I’m going to dealership this morning anyway (I’m order some seals for the transfer case which is leaking).
How did you make out with this project? Im going through a timing cover reseal because of a major oil leak.
 
How did you make out with this project? Im going through a timing cover reseal because of a major oil leak.

My engine runs with no leaks so I guess it was a success :)

I had the engine entirely out of the car (since I was rebuilding it) so doing the timing cover was easy. But the first time I had the cover off with the old engine still in the car I thought it was a real pain to deal with the sealant. I remember reading on here from someone (maybe @JohnnyTightlips ?) who found a gasket or asked a company to make a gasket for the timing cover. That would be a lot easier. If it matters to you I think I used the black rtv the last time as where the first time I used the red.
 
Thanks Johnny :) I have done it once before although I didn’t loosen the cam bolts. I should do it this time and I just happen to have two friction washers.

I see in the other thread it looks like you have a new front oil seal. Do you think it should be replaced each time?
Did you have any problems with the timing chain tightness when you didn’t loosen the cam bolts and put it all back together?
 
Did you have any problems with the timing chain tightness when you didn’t loosen the cam bolts and put it all back together?

Not that I could tell. I’m not saying it was optimally tight but it was tight enough not to have issues. Loosening the cam bolts wasn’t a big deal though the second time. Just extra hassle cleaning up stuff and then getting the friction washers.
 
Not that I could tell. I’m not saying it was optimally tight but it was tight enough not to have issues. Loosening the cam bolts wasn’t a big deal though the second time. Just extra hassle cleaning up stuff and then getting the friction washers.
Did you reuse the bolts on the cams?
 
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