Hi
My bro has a dead Astra diesel with a failed water pump that's broken the cambelt (says the RAC man). He lives a long way from me so I need to know a bit more about Astra Diesels before I go over to fix it for him....
Seems there are two engines a Vauxhall and Isuzu. How can you tell them apart (He sent me a pic and his has DIESEL written on the cam cover and a big air filter box on the left).
In addition to the water pump and belt, is it likely to need valve replacement?
If it needs valve replacement can you take the head off with the manifolds in place?
I just need to figure how long the job will take.
Tks Stuart
Edited by Webmaster on 11/02/2008 at 23:08
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Stuart
Engine size 1.7? [He'd have a hard job to break a belt on a 2.0 ltr?]
Sounds like a X17DTL GM unit. There's a 99% chance of big damage; strip everything and check carefully before buying any parts. Re-con head is your best bet - but check the deck heights first.
Right pig to do and set up; you need a dial gauge and a load of setting tools. A full days work.
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It will be the GM engine. It depends on whether or not it has genuine rockers. Remove the cam cover to see if any are broken, and if any have you may be in luck. If they are genuine they will often break, which means although the pistons will hit the valves the rocker will break on impact ,and you will often just need to replace the broken ones. There is a special tool to do this, and Draper, Kent Moore, and Sykes Pickavant all do it. The Draper part number is 33607_373. Click on this link for a picture. img526.imageshack.us/img526/1750/33607373sk1.jpg
If the rockers are non-genuine then you will have to remove the head and replace a couple of bent valves at least.
It's much easier to remove the inlet manifold and unbolt the exhaust manifold first when taking the head off. That way you don't need to disturb the turbo. Just remember that there is a bracket bolted to the back of the engine block which you will need to remove to get the exhaust manifold out the way. Incidently the job is not difficult to do on these, and you shouldn't encounter too many problems......
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Tks for the help on this.
Yes, it's 1.7 (now added up top) and definitely a GM. I can get bro to check under the cam cover and see how it looks before I go over there. If there's a few rockers broken we can take a first chance on replacement rockers and fixing the belt, pump etc.
Stuart
Edited by Webmaster on 11/02/2008 at 23:08
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Bro checked in cover today and looks like ALL the rockers are broken. Suspect the belt teeth stripped and timing slipped when the water pump seized. We'll take a chance replacing the rockers, belt and water pump and see what happens.
Tks again
Stuart
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to make life easier don't forget to squeeze the hydralic lifters as the valves are straight in the head you would be extreamly unlucky to bend any valves
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to make life easier don't forget to squeeze the hydralic lifters as the valves are straight in the head you would be extreamly unlucky to bend any valves
Good advice here. Either remove the clip on each follower in turn and clean them out, or squeeze then in a vice to remove the oil. Put them back with only a very light coating of oil so that you can press them with your fingers. If you don't do this the engine will be very difficult to start at best......
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Another thought. Do not remove or slacken the camshaft sproket bolt. Is is tapered, and not on a locating peg. If you don't slacken it you won't have the problem of setting up the valve timing, other than to fit the new belt, and therefore can only be wrong by at least a whole tooth or teeth.
There is a mark on the crankshaft sprocket, and a corresponding mark on the oil pump housing at 6 oclock. This will be TDC No.1 & 4. There is no mark on the camshaft sprocket to line up though, unless someone previously has made one when the cambelt's been changed (I always put a centre dot on the pulley, and made a very small saw cut in the casing when I did them).......
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These engines need setting up with the tool & very acuratley as they only have 1mm clearence betwwen valve & pistons when timming is correct. Don't guess it! use the tools & if any doubt do not start it as reving will break the new rockers unless the timing correct.
When the timing is set the engine should be turned over by hand twice & re-checkled before starting.
Inj Doc
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sq
Very true Injection Doc, and even more reason not to slacken the camshaft sprocket bolt. Only an idiot can get the crankshaft in the wrong position, but like IJ said the camshaft is possible to look like it's right even when it's actually a tooth out, so measure it to be sure.
We used to have a Kent-Moore camshaft locking tool when I worked in the dealer, and although it was designed for the 16D and 16DA engine it would fit and time the 17DTL correctly, even though only two of the three bolt holes would line up.....
Edited by Pugugly {P} on 17/02/2008 at 21:13
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it was designed for the 16D
If I remember correctly, the locking tool was only strictly meant for the 16D.
For the 16DA and later engines, you were supposed to slacken the camshaft sprocket, and set the cam with a dial test indicator.
I knew that the locking tool worked for the 16DA, although those who had been on the Vauxhall course said that using it for a 16DA was a bit dodgy. I didn't know that it could be used to time the 17DTL though.
If I were stuck in the desert, I suspect I would slacken the cam sprocket, with 1 and 4 at TDC, I would gently rock the cam back and forth until the valves hit, and then set the cam halfway between the inlet hitting and the exhaust hitting.
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hope this desert place has plenty of rockers in stock, i know what you mean been there and tried it only true way to go is with the right kit best thing would be to do all the work get every thing sorted and tow it to a diesel specialist to get it right first time, may cost more than you want to but would be cheaper in long run,rockers, aggro, time etc
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>>only true way to go is with the right kit
Fully agree, and I wouldn't suggest the OP should try anything else.
The "desert method" is very much a cheat, and would almost certainly result in incorrect cam timing.
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