DIY Timing Chain

[myoldhk]

12. Before you do anything else have a break
13. loosen all bolts and nuts on gears with chain and tensioners in place easier to undo but don’t remove. T70 bit for main gear and 4 hex bit bolts
14. Put pin in 2 tension rods as per guide
15. Remove the balance gear, and then tension guides.. (don’t lose moon pins)
16. Remove top chain.
17. Swap sprockets on cam (keep in alignment.)
18. Remove bottom sprocket on crank along with main sprocket slowly not to knock anything out of alignment. And remove 6mm then put back in when gear removed.

If you bought the yd25 kit just swap gears on vacuum pump bottom left under main gear. And tighten up. Goto 23.
19. If you bought kit for vacuum pump it’s a prick to get to 3rd bolt. Follow guide NEED sir clip pliers
20. Remove brackets on back 4 bolts, and undo 3 bolts on vac pump, the loosen injector pump e-torx bit and move it back to get vacuum pump out. AS PER GUIDE.
21. Rebuild https://www.youtube.com/watch?v=GqaFeSS_8hM (fins must be in place correctly when lid goes back on as they will break, and everything inside MUST BE CLEAN)
22. Put back in. do up vacuum pump and injector pump
23. Put crank gear on most of way
24. Put new chain on new main gear and align with crank gear and slide on as one.
Chain should be loose enough to move a tooth or two if needed.
Note: I aligned the tooth and chain from old one with markings before putting on
25. Align bottom gears, put top chain on and align.
26. Put all tensioners and guides on and pull pins from new tensioners and tighten up all bolts as per torque settings.
27. Tighten all gears (as tensioners are on its easier to torque up. (CAM IS, 142.1NM I got about 135nm)
28. Align Balancer gear on crank with gear you marked under crank and put COAT HANGER WIRE in gear to hold whilst balancer goes on.
Chain should be aligned and time to put back together.
29. clean primary case, put new seap and then gasket goop up and put on and tighton to spec.
30. Crank pulley on next and tighten to 75nm then mark out 120deg and tighten the further 120deg. (I only could get 90deg out of it with my 2m extension on the breaker bar.
31. Secondary case clean and put back on and torque up.
32. Then pulleys and radiator etc etc till it’s back together.

 

[myoldhk]

oil and coolent then start and fingers cross!

 

[myoldhk]

Issues
Tools are an extra cost (but I now own a good set)

Crank bolt IS TIGHT as F#$%

Vacuum pump, crap spot or a good few hours extra work and an extra cost at wreckers if break the fins. They must be out to wall when lid goes back on. (YD25 has sprocket that fits old shaft EASIER and less time)

Kit guides are crap, too big and sloppy (guessing yd25 use the same ones tho)

3 bolts from sump must be removed to get off primary case other you crack it and a trip to the wreckers or weld repair.

Then oil leaks I’ve got 1 only and it’s on the primary case and its staying there for a while. Must have missed a bit of goop.

Snapped 2 bolts as I forgot to push reset on torque wrench

Apart from those small issues my fault, its pretty straight forward, and remember wreckers aren’t open Sundays, so if you stuff it you wait.

 

[nuckin futs]

myoldhk i was speaking to paul at yd25 and he said that the extra 120 deg is important. found this on their web site. would hate to hear of something going wrong after all the work and money you put into yours. this is from their web site incase you havent seen it." the shearing of the crankshaft timing sprocket wood drift key due to not torquing to 55 lb + 120 deg will not be covered by our warranty, the installer will fully responsibility for their workmanship." im sure someone on here will know more about this than me and can elaborate. also be careful of a double row timing chain kit on ebay for $1060. its a cheap import and even uses the name yd25parts.com and is based in mooloolaba. they may be ok but dont go thinking your getting a kit from yd25

 

[myoldhk]

I agree it possibly could be important. And I did 75nm or 55ftlb and about 90 deg but with the amount of force I used to get it. I doubt it many people could. Even tried rattle gun to no avail. But I have to undo it soon im sick of the little oil leak I got, and will be trying it again.

 

[myoldhk]

Stripped it down again to re-goop leaky spot around one of the bolt hols on the primary timing cover.
Left radiator in, coolant and oil in. it is possible to do, but space is bit more limited to do the conversion/ changeover of timing chain. what I did get is a 75nm and 120deg turn on the crank bolt and lucky I have strong legs, arms no good to get this turn.

What I did discover is that the gasket goop after a week was actually still wet and didn't set. so im trying a different brand.

 

[camo.b]

Good to hear..There is usually 2 types...hard set and soft in goop.what brand you running

 

[myoldhk]

First one was thredbond 1215
And this time permatex ultra grey which seems to have done the trick just nicely

 

[sparra04]

thanks for the time and effort on the diy
much appreciated by all who will use it

cheers

 

[myoldhk]

No worries, I'm a big fan of giving stuff a crack, especially when it costs a mint to do. (Cost is in the labor) And if you have a bit of an idea, can research and have the time it's really not a hard job, just very time consuming.

 

[Diesel Marks]

Nice write up mate! I have just done the timing duplex chain and tensioner on mine (genuine Nissan) and when I put it back together and started it up it is 10X noisier and rattly? Any ideas what could have happened? We are stummped to what it could be...

 

[Navmania]

Could be a number of things. Just wondering why you changed the cam chain only. It's normally the primary chain that gives the problems. The tensioner didn't have a pin in it to hold the piston back did it.

 

[nuckin futs]

did you prime the tensioner before you installed it

 

[Diesel Marks]

Could be a number of things. Just wondering why you changed the cam chain only. It's normally the primary chain that gives the problems. The tensioner didn't have a pin in it to hold the piston back did it.

Yeah it had a pin in it. We also primed the tensioner with oil as well. Only changed the cam one to try an isolate the problem first before spending more $$. Parts weren't available for the rest of the kit at the time.

 

[Navmania]

Cool, no probs. that's all I could think it could have been.

 

[nuckin futs]

think id be taking the cover off and giving it a run and having a look just to be safe. might get a little bit of oil spraying out

 

[myoldhk]

Did the rubber o ring when you put the primary (bottom) cover fall out? There are 2 a black and a orange one.
What I mean is its the seal for the oil to pump to the top.

 

[Diesel Marks]

myoldhk, I only did the duplex as the piston was pushed way out and the measurements were 17thou instead of 15thou. Its like its not getting oil to the tensioner?

 

[myoldhk]

Could it possibly be the chain is 1 link longer on the tight side and not straight.
Leave the top sprockets and chain and move the chain 1link on the bottom sprocket.

Mine rattled for a couple of minutes until oil got to it.

 

[Diesel Marks]

It sounds like a really old diesel rattling now. only ran it for 30 seconds max!
Is it ok to have turned the primary chain backwards to get chain on? all timing marks lines up but there is no factory mark on the crank pulley?