Newly built CIH, how hard should it be to locate the timing chain sprocket onto the cam end?

[611]

I have finished building my 2.4 CIH

All news bits, new timing chain, new timing chain tensioner and chain guides, new cam new pistons, its pretty much a new engine.

Now when i drop the head on and lightly torque it down and go to locate the vernier wheel onto the cam end, its a fair way lower and there is no way it will go on by hand. I have removed the chain tensioner and if i pull the chain and wheel up by hand it a good 2-3mm lower and i dont want to force it on as im sure then it will be putting quite a bit of pressure on that front cam bearing (which are all new)

The chain was an aftermarket one i got from Opel GT Source as could not find a genuine one.

How tight should it be to put on?

I have spent  load of money on the engine and dont want to Fu** it up by forcing it on!

I think i have the old chain but will have to break the engine down to test it out.

 

Any info would be great to help decide what i do next.

Thanks

Andy

[hoobby]

It may be the chain has dropped down under the crank cog so you have too many links down there giving you the short chain.make sure all valves are closed    then lift the vernia wheel tight by hand and turn the crank pulley gently 1/2 a turn if you feel firm resistance stop the chain has snagged.also count the links on old chain and new see if they are the same.

Edited April 27, 2019 by hoobby
Chain links

[H-400]

Never had this before, so something must be wrong. What Hoobby advises is also my idea.

If that doesn't help you'v got to open it again. 

[611]

Hey Guys

Thanks for the advice, i decided to remove the front cover and get the chain off and it looks to be the same length. Will try and do a proper measure tomorrow.

And i might test the old chain on tomorrow and see how that works. How much slack should there be with the chain pensioner out?

I dont suppose anyone has a pic of one they have to show how much movement i should have?

 

If it works out that the old chain sits in the same place maybe its the chain guides? as they are not genuine ones.

Any other thoughts?

 

Andy

1 hour ago, H-400 said:

Never had this before, so something must be wrong. What Hoobby advises is also my idea.

If that doesn't help you'v got to open it again. 

Herman

As you have just been building a CHI do you know how much movement i should have in that chain? If you have the tensioner out and pull the chain and wheel up should it just go onto the front of the cam or does it have enough play to actually pull up and go beyond the cam, im just trying to figure out what is making it tight and how much tighter than normal it is?

Thanks

Andy

[H-400]

As I can remember you have just enough space to put the wheel on the cam, but you can check the tension of the chain.

That is something I have to look after, got it in my technical manuals.

Will give you the info if you want to, 

grts, Herman

[611]

26 minutes ago, H-400 said:

As I can remember you have just enough space to put the wheel on the cam, but you can check the tension of the chain.

That is something I have to look after, got it in my technical manuals.

Will give you the info if you want to, 

grts, Herman

Thanks Herman. Any info will be good. Im going to try the old chain tomorrow and if its still the same im going to look at the guides in case they are the issue. I have found 2 of the 3 guides on a site that say they are genuine GM ones so i have ordered those anyway to see if there is a difference. I have spent enough getting it this far so for a few more pounds its worth a try 🙂

Andy

[cam.in.head]

Never had this issue either and mr Hoobys answer Seems the most likely.

otherwise.

 

The chain when pulled up with the top cog should rest against the right hand guide.parrallel.this is only there to stop the chain slapping sideways into the cover and should not deflect the chain inwards.the left hand top guide is the one that takes up and holds the chain inwards to stop any slack before the tensioner arm.the tensioner arm when the tensioner is not in will stay back pretty much out of the way so any non genuine guides would have to be very obviously different from the originals(never had an issue here) or fitted incorrect 

make sure the top guide has seated in its little ball shaped recess .you will see what I mean.

 

The top wheel should sit a good few mm above the end of cam when Lifted with no tensioner in

[611]

52 minutes ago, cam.in.head said:

Never had this issue either and mr Hoobys answer Seems the most likely.

otherwise.

 

The chain when pulled up with the top cog should rest against the right hand guide.parrallel.this is only there to stop the chain slapping sideways into the cover and should not deflect the chain inwards.the left hand top guide is the one that takes up and holds the chain inwards to stop any slack before the tensioner arm.the tensioner arm when the tensioner is not in will stay back pretty much out of the way so any non genuine guides would have to be very obviously different from the originals(never had an issue here) or fitted incorrect 

make sure the top guide has seated in its little ball shaped recess .you will see what I mean.

 

The top wheel should sit a good few mm above the end of cam when Lifted with no tensioner in

Thanks, this really helps me out, not fixed but i have an update!

OK, so this is where im at now.

Took head off and front cover, checked new chain with old chain (which in 99% sure is from when i stripped the engine originally) the look exactly the same length (but how you would accurately measure im not sure!)

With the head just placed on and not torqued down, only the long right guide in the old chain with the top cog in does go a good 3-4mm above the cam end. The new chain is close, probably 2-3 mm over.

Now with the cam wheel fitted onto the cam, if i put the cover on with the top left guide in (i have checked its seated ok, should it have a cir clip holding it in?) i can just jiggle it on and with a bit of persuasion get the cover bolts in, the chain is tight but it does turn over ok, BUT if i try the new chain i cannot get it on without a lot of force and it is very tight. 

Now i know this is not the right way but im just trying to figure out if its the guides or the chain? I have ordered the top guide and the right guide from these guys https://www.genuinepartsearch.co.uk/ and they say the are genuine,s o lets see! Now got to try and find a genuine chain to test as well.

Any more info on my update would be great.

 

Andy

[H-400]

Hi Andy, sorry for the late answer. Been whole day on the road with the "400", was a nice meeting.

Am looking for more info, but what I remember is that the length of the tensioner must be 2mm longer than compareble distance you measure 

From the house to the guide your tensioner pushes. 

But I think this is not your problem. Think it is normal a new chain is a bit shorter than a used one, so I think there is maybe a problem with the new guides/tensioner guide.

I'm sure there were giudes of the wrong design. So I would compare them with your old ones.

I have a complete new set in my garage from Thomas Edelschmiede and they look as this:

Got the old ones also still in the dis/cover. When I'm free tomorrow I will have a look at everything.

Edited April 29, 2019 by H-400

[®evo03]

I am a total novice at engine building, well cih anyway, must be a strong engine!, but.......can you link the old and new chain, thats if you get the old chain fitted, interesting thread that i hope i never need. 

I built a few bike engines, and had issues setting timing chain on a r6, worked out had to offset the timing before torque setting, once torqued all was fine. 

Would the thinkness of the gasket affect CIH engine. 

Edited April 28, 2019 by ®evo03

[H-400]

Took some pics of the cover with the old and new guides. The old ones are original GM, and I changed them 10 years ago lets say 15.000km back. Bought them at our local Opel Dealer. The new ones are from Thomas Edelschmiede and they look the same:

I remember there was a problem with some sets (not from Thomas) cause the bottom-left guide was wrongly designed.                                                                                                                            This is zoomed in so you can see there is a spring on the rotating pin to keep the tensioner-guide on its place. Look also to the round mark (left) that the chain-tensioner made after not so many km's:

Just a detail but important: If you buy some stock left over gaskets be sure you use the good gasket of the timing cover. The gasket of a 6-cil. 24V is almost identical but your engine will have an oil problem and your bearings WILL die! Pic of the proper one:

[hoobby]

Are you sure it's the correct chain?.count the pins in each chain it will give you the lenght.also check that the chain seats properly down snug on the cam sprocket.

Edited April 29, 2019 by hoobby

[cam.in.head]

Just one more thing. 

When you say you have put the head on but not torqued it up yet I assume you don’t mean the head bolts are slack ?

Sorry here if I’m stating the obvious but I assume the head bolts are tightened (at least a bit anyway) otherwise the front rubber o ring in the top of the timing cover would hold the head up a bit !. Sorry again as I don’t think you will have this problem but was worth mentioning.

otherwise comparing new and old parts and positions with the engine pictures in a Haynes book SHOULD show what’s gone wrong/ is different etc.

never seen or had this issue so should be something obvious

 

[andyc]

Did you have the hydro tensioner screwed in the the first time you tried to the the sprocket to the cam, if so it wont fit, take the tensioner out fit the sprocket and fit the tensioner

 

Andy

[611]

2 hours ago, cam.in.head said:

Just one more thing. 

When you say you have put the head on but not torqued it up yet I assume you don’t mean the head bolts are slack ?

Sorry here if I’m stating the obvious but I assume the head bolts are tightened (at least a bit anyway) otherwise the front rubber o ring in the top of the timing cover would hold the head up a bit !. Sorry again as I don’t think you will have this problem but was worth mentioning.

otherwise comparing new and old parts and positions with the engine pictures in a Haynes book SHOULD show what’s gone wrong/ is different etc.

never seen or had this issue so should be something obvious

 

Head just nipped down but not fully torqued. When i last put the engine together it was all fully torqued down with chain tensioner out and it was so bloody hard to get on, which is why i think i had the problem with the front cam bearing as it would have really been pulling down on the front of the cam. I dont have the old parts (or they are in a safe place!) only the chain and comparing those they have the same amount of links and look the same length. If i had the old guide rails then i could do a compare of those as im wondering if the top one is not 100% correct as with it off its an aftermarket one but the number on it does not match the number for the same make when i google, looks exactly the same but without one to measure i cant be sure.

2 hours ago, andyc said:

Did you have the hydro tensioner screwed in the the first time you tried to the the sprocket to the cam, if so it wont fit, take the tensioner out fit the sprocket and fit the tensioner

 

Andy

Hey Andy, your engine looks nice 🙂 Got chain tensioner out and head bolted down but not torqued to the full spec as i was doing this as a test fit as last time it was very tight to get on and i think that might have caused issues, the more i look at parts the number on the top guide does not seem to match with google searches. That part number does not come up at all? and i dont have the old ones to test, i have the old chain and that looks the same and will just go on but is tight (i presume its stretched after 70'000 miles so will be slightly longer but still doesnt seem right. problem is i bought all the parts years ago so dont know who they came from and i cant seem to get genuine parts as that would be the ideal solution as i would know all ok.

[andyc]

The numbers won't match anything genuine as they are repo parts, did you get the kit from Opel GT Source?. I've use Gils kit on the Senator engine. It wont just push on but will need a tap to help it, i just used a hammer handle to tap it in place

 

Andy

[611]

I think it might have been Gils, all his bits have been good. I know the aftermarket one wont have a number to match the original but that number doesnt even come up on their site? and its the only thing that i can see that could cause the problem. I have ordered another aftermarket chain that i saw on TJ motorsport that says its a piper CIH duplex chain (lets hope they have it in stock!) so when i get this that will give me a reference on the chain and if that wont go on with these guides it must be the guide.

With the new chain and guides in its not just a tight fit to get it onto the cam (same issue with the old original cam) yo have to leaver it up to get it in line and then knock it on. See very rough pic. That is with me pulling it hard up by hand?

 

Andy

 

 

[H-400]

That guide you showed looks OK, my guides have that same thickness on the other side. Look at the pic of Edelschmiede.

Maybe stupid question but I never tried, is it possible the bottom gear on cranckshaft is reversed/moved? The gear of the oil pump/distributor 

goes easy of but think to move the other one you need a puller...

[paulmanta]

Is that the original top cam wheel ? 

The pic makes it look like the drillings are out of line.

[H-400]

Think it looks like an adjustable one, with those bolts on it. The original looks like this;

And this is an example of an adjustable one:

If so I would try an original one

[611]

Thanks for the info guys. Its adjustable and was on my 2.0l so should be the same. I will take a look at how my guides site, looking at yours Herman, mine seemed to sit a little further out and not right up afainst the case like yours (the adjuster side) just for info this is what Thomas said about the pic of my guide.

The picture from the curved guide is made by SWAG, this is original quality, they made the guides for Opel. – I heard about the same problem from another customer, but I don’t heard the solution for this problem

Think i might have found an original top cam wheel and have ordered another chain so i can check it all out and trying to get original guides to test, i will get pics tonight and compare.

 

Andy

[H-400]

Keep us informed, this is important for all forum-members that want to overhaul their engine.

[Exclusive Opel]

Don't know if this is any help for reference. These are not genuine ones but are new.

[cam.in.head]

Everything else appears ok and standard so hopefully the difference will be in the top cog. Maybee the adjustable one is a sligthly bigger diameter.you will see when you get an original solid one

got plenty here if you need one

Edited April 30, 2019 by cam.in.head

[611]

2 hours ago, H-400 said:

Keep us informed, this is important for all forum-members that want to overhaul their engine.

Herman, that pic of your really helps. Look at mine. Its sits slightly further out, only 1/2mm but if you push it from the side at the cover it wont push right against the edge like yours? not sure if that is the issue or not will see. I now have a new chain coming from piper, and found a new old stock kit in Italy that has top cog, bottom cog, right long guide and new chain. Its was listed as a kit with part number and all the referencing i could find say it will fit a so lets see. If not i will have to try and find exactly what its for and sell it 🙂 the guide is right and i will just use the top cog for reference so if it is the right one for a cam in head i will have a new cog for sale 🙂 should be here next week so i will keep you all posted.

Andy

2 hours ago, cam.in.head said:

Everything else appears ok and standard so hopefully the difference will be in the top cog. Maybee the adjustable one is a sligthly bigger diameter.you will see when you get an original solid one

got plenty here if you need one

Thanks for the offer. Not sure as i ran this same cog on the 1.9 with no issues but all the other parts were genuine GM so no reason to suspect the cog so that is what i find strange. I know this is the 2.4 but they seem to list all the parts as the same unless i have missed something?

3 hours ago, Exclusive Opel said:

Don't know if this is any help for reference. These are not genuine ones but are new.

Thanks for the pic, i suspect it to be the top right in your picture that might be the issue if its not the chain, what is the depth in the middle? the bit where the number 9 sitsas if that is deeper on mine it would push it out enough to make the difference. I might be wrong and find out when i get the chain its that, lets face it there are only a few parts it can be 🙂