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Old 07-15-2021, 10:27 PM
v8volvo v8volvo is offline
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Join Date: Jun 2009
Location: Montana, USA
Vehicle: '86 745, '83 764
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Quote:
Originally Posted by ngoma View Post
And more importantly, according to your photo, if the belt jumped the teeth on the sprocket, the IP sprocket mark would be on the other side of the IP and bracket marks, because of the engine rotation direction.
Good point. According to that photo it does look like the pump is off time but in the advanced direction. I guess in theory this could happen when shutting off the engine depending on where/how the engine and IP stopped turning.

Quote:
Originally Posted by DylanW View Post
I believe the cam timing is correct cause when I line up the zero mark on the flywheel the mark on the cam sprocket lines up with it's timing mark.
On some engines, the logic of what you are saying here would be right on. BUT on this engine (like many diesel engines and some gas engines also), the cam sprockets are NOT keyed to the camshaft. Neither one of them -- the front or the back. They can be installed on the cam in any position, and are affixed by taper or flat friction fit. The purpose of this is to allow an infinite range of adjustment for cam and IP timing. Necessary because the diesel engine demands this level of precision, and timing it just to the closest tooth on the belt wouldn't have been exact enough.

So what that means is that the mark on the rear cam sprocket doesn't really mean anything. The only reason it even exists is that VW cleverly use the exact same sprocket on the back of the cam and on the IP, just mounted facing the opposite direction, and thus it has to have a mark for where it's installed on the IP. But on the cam, that notch serves no purpose and should just be ignored so as not to cause confusion.

Unless you are talking about marks on the front cam sprocket? That sprocket has no marks from the factory, so maybe you are talking about paint marks? If paint marks are what you are seeing, then it's perhaps good news that they line up. But the bad news is that those marks were made by a human mechanic sometime, during a stumbling attempt to replace the timing belt, not by the factory. So their accuracy is only as good as the guy who marked it made them. And the fact that they are there almost always means the timing belt was done without the correct tools and process. And THAT probably means the front crankshaft harmonic balancer bolt is not as tight as it should be.

Quote:
Originally Posted by DylanW
I also tried to retime the IP but afterwards the engine wouldn't even idle just start up and die. So I timed it back to what looks to be a tooth off but it runs much better and is able to idle.
....
Should I check the IP timing using a dial feeler gauge or leave it as is cause it seems to drive like before but even before at probably 3/4 throttle it's shoots out black smoke. Thanks
How were you timing the pump? By loosing the mounting bolts and rotating it, and doing visual timing with the marks?

Strongly again suggest getting your hands on a copy of the D24 "greenbook" Volvo factory manual. Well known on here to be worth every cent, full of extremely helpful info. After you read the sections on timing belt replacement, etc, it will help the engine make a lot more sense. Looking on ebay right now there are many out there, costing $20 or less with free shipping. The best money you will spend on this car by far. They are EASY to work on the right way, but can get you in trouble if you try to just feel your way through it using accustomed methods learned on other engine designs.

Think of it like an aircooled VW versus a small block Chevy -- it's not more complicated or harder to fix, but it IS different. Putting in a little time up front to understand how it is designed will pay you back many times over as you work with it.

I would check the torque on that front crankshaft dampener bolt before thinking about anything else. You need special tools for it -- that manual will be your friend to show you the process which is very simple and easy. If you need the special tools they are available to borrow on this site for free.
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