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  #11  
Old 12-27-2020, 02:45 PM
Sethsquatch Sethsquatch is offline
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OK so my mechanic came by in a Saturday, and looked at the engine. He said it's jumped time. I don't exactly know what that means, but he said the pump could be way out now. The Pinz wouldn't even start, just blew tons of smoke. Does this sound like an accurate diagnosis? He is going to come to my house and fix it here which is nice....
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  #12  
Old 12-27-2020, 05:56 PM
v8volvo v8volvo is offline
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Quote:
Originally Posted by Sethsquatch View Post
He said it's jumped time. I don't exactly know what that means, but he said the pump could be way out now. The Pinz wouldn't even start, just blew tons of smoke. Does this sound like an accurate diagnosis? He is going to come to my house and fix it here which is nice....
Yes it absolutely sounds accurate. In fact it is exactly what we expected to hear, based on the noises and change in engine operation you described. Those are textbook symptoms of an engine coming out of time.

What he means by "jumped time": this means a timing belt or a timing gear slipped, due to the installation having been screwed up. It's not something that just happens for no reason. It's because a mechanic got belt tension wrong, or incorrectly installed a component, or didn't correctly torque one or several of the camshaft or crankshaft center bolts causing one of the three timing gears to slip. Commonly seen reasons why these things would happen are attempts to do the job without the correct tools, the correct information, the correct experience, or without all three.

The key question now is whether it jumped time on the camshaft timing belt, or the injection pump timing belt. These engines, like many others, have both. Jumping time on the IP belt will cause the engine to run poorly or not at all, but doesn't lead to long term harm. If that's what happened, then you got lucky. However, jumping time on the camshaft belt, like on any diesel engine (and almost all gas engines as well), is a major disaster that always results in internal engine damage. If that is where it came out of time, then the engine needs to be disassembled again and probably will need another cylinder head rebuild, at minimum.

Needless to say, cross your fingers for the lucky scenario. But regardless, the fact that this happened should serve as a big red warning sign about all the other work that was done on your engine. More problems could occur for similar reasons of incorrect technique and/or equipment, and some of those other problems could be much more catastrophic, destroying the engine or even putting you as the driver, or other vehicles around you on the road, in danger.

Before having your mechanic go any further, you want to ask some friendly questions.
Start with these:

1) What was the technique and specific tools used to install the front bolt on the crankshaft? And what torque spec did he use on that bolt? Sourced from what information? Best would be to ask him to send you a photograph of the tools he used, and then post that here. This will tell us, and you, a great deal.

2) Which belt does he believe slipped? And WHY did it occur, from his point of view?

3) What is his plan now for fixing it such that it won't happen again? What does he intend to do differently this time?
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  #13  
Old 12-28-2020, 10:12 AM
Sethsquatch Sethsquatch is offline
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So it is the injection pump that slipped. He said he (of course) didn't have the tool to do it, but had something similar that he thought worked and had it tight. Obvi not.
So now, my question is, where can I find those speciality wrenches for the injection pump, I saw the thread with pics of them, but can I buy them somewhere? Anyone near Denver with a set I could rent? Much appreciated!

Seth



Quote:
Originally Posted by v8volvo View Post
Yes it absolutely sounds accurate. In fact it is exactly what we expected to hear, based on the noises and change in engine operation you described. Those are textbook symptoms of an engine coming out of time.

What he means by "jumped time": this means a timing belt or a timing gear slipped, due to the installation having been screwed up. It's not something that just happens for no reason. It's because a mechanic got belt tension wrong, or incorrectly installed a component, or didn't correctly torque one or several of the camshaft or crankshaft center bolts causing one of the three timing gears to slip. Commonly seen reasons why these things would happen are attempts to do the job without the correct tools, the correct information, the correct experience, or without all three.

The key question now is whether it jumped time on the camshaft timing belt, or the injection pump timing belt. These engines, like many others, have both. Jumping time on the IP belt will cause the engine to run poorly or not at all, but doesn't lead to long term harm. If that's what happened, then you got lucky. However, jumping time on the camshaft belt, like on any diesel engine (and almost all gas engines as well), is a major deal that always results in internal engine damage. If that is where it came out of time, then the engine needs to be disassembled again and probably will need another cylinder head rebuild, at minimum.

Needless to say, cross your fingers for the lucky scenario. But regardless, the fact that this happened should serve as a warning about all the other work that was done on your engine. More problems could occur for similar reasons of incorrect technique and/or equipment, and some of those other problems could be much more catastrophic, destroying the engine or even putting you as the driver in danger.

Before having your mechanic go any further, you want to ask some friendly questions.
Start with these:

1) What was the technique and specific tools used to install the front bolt on the crankshaft? And what torque spec did he use on that bolt? Sourced from what information? Best would be to ask him to send you a photograph of the tools he used, and then post that here. This will tell us, and you, a great deal.

2) Which belt does he believe slipped? And why did it occur, from his point of view?

3) What is his plan now for fixing it such that it won't happen again? What does he intend to do differently this time?
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  #14  
Old 12-28-2020, 05:45 PM
v8volvo v8volvo is offline
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That's good news.

But here's the thing: don't worry about the injection pump timing right now.

For a moment, forget about this immediate problem (which may well have saved your entire engine, by disabling it before other more serious things could go wrong), and instead focus ALL of your attention first on the FRONT CRANKSHAFT BOLT.

Why do we keep harping on this, even though it is not the direct cause of the truck not running right now and is NOT the question you asked about?

Because if your guy didn't have the tool or correct method to successfully tighten the rear camshaft bolt, then it is almost certain that he didn't have the ability to successfully torque the front crankshaft bolt either. Again, you should ask him what he did and maybe we'll be pleasantly surprised. But the answer is probably that he attempted to "get creative" with that part too.

If that bolt is anything less than exactly as tight as required, then it WILL come loose. The torque spec is about 350 ft-lb -- probably tighter than any fastener your mechanic has ever installed in his entire life, and probably almost DOUBLE the maximum value his torque wrench reads up to. Guys try to do it "by feel" or with a big impact gun, but that will not get them close. They also try to do it using the transmission to hold the crank in place, but that doesn't work either -- it will break the gearbox or slip the clutch before you reach the target value. There is no way to do it except with the right method and equipment. If the bolt does comes loose, then it will at minimum destroy the entire top end of the engine and usually the crankshaft also. Sometimes worse. It will be a very sad day not just for you, but also for your mechanic if this happens.

That's the warning. Don't start with the repair to get the truck running, even though it will be very tempting to begin there. Don't do it. First, get this part right.

THEN, proceed to have every other part of the front timing system and process double-checked again, this time following the factory instructions to the letter and using all the right tools. ALL of them. This includes cam timing, idler pulley installation, front camshaft bolt torque, etc.

Then, finally, once you/he are sure that the engine is not sabotaged anymore, proceed through the full injection pump timing process to get the engine running again.
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  #15  
Old 12-28-2020, 06:04 PM
Sethsquatch Sethsquatch is offline
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Great advice. And again, something I didn't know. I spent the day calling a dozen Volvo and Volkswagen shops in Denver asking if they were familiar with this engine, with no luck.
So that being said, obviously there's special tools for the crankshaft in addition to the injection pump. Where do I find these?
Is there an alternative that can be used?
How do you even measure 350 lbs on the nut?



Quote:
Originally Posted by v8volvo View Post
That's good news.

But here's the thing: don't worry about the injection pump timing right now.

For a moment, forget about this immediate problem (which may well have saved your entire engine, by disabling it before other more serious things could go wrong), and instead focus ALL of your attention first on the FRONT CRANKSHAFT BOLT.

Why do we keep harping on this, even though it is not the direct cause of the truck not running right now and is NOT the question you asked about?

Because if your guy didn't have the tool or correct method to successfully tighten the rear camshaft bolt, then it is almost certain that he didn't have the ability to successfully torque the front crankshaft bolt either. Again, you should ask him what he did and maybe we'll be pleasantly surprised. But the answer is probably that he attempted to "get creative" with that part too.

If that bolt is anything less than exactly as tight as required, then it WILL come loose. The torque spec is about 350 ft-lb -- probably tighter than any fastener your mechanic has ever installed in his entire life, and probably almost DOUBLE the maximum value his torque wrench reads up to. Guys try to do it "by feel" or with a big impact gun, but that will not get them close. They also try to do it using the transmission to hold the crank in place, but that doesn't work either -- it will break the gearbox or slip the clutch before you reach the target value. There is no way to do it except with the right method and equipment. If the bolt does comes loose, then it will at minimum destroy the entire top end of the engine and usually the crankshaft also. Sometimes worse. It will be a very sad day not just for you, but also for your mechanic if this happens.

That's the warning. Don't start with the repair to get the truck running, even though it will be very tempting to begin there. Don't do it. First, get this part right.

THEN, proceed to have every other part of the front timing system and process double-checked again, this time following the factory instructions to the letter and using all the right tools. ALL of them. This includes cam timing, idler pulley installation, front camshaft bolt torque, etc.

Then, finally, once you/he are sure that the engine is not sabotaged anymore, proceed through the full injection pump timing process to get the engine running again.
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  #16  
Old 12-28-2020, 09:44 PM
v8volvo v8volvo is offline
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Quote:
Originally Posted by Sethsquatch View Post
again, something I didn't know.
Well, that's not your fault.

The point of bringing a job like this to a professional is it becomes THEIR job to have this kind of knowledge, so that you don't have to. Right? You pay them, rather than doing it yourself, because 1) they already possess the expertise, resources, and equipment needed to do the work successfully and professionally, or 2) if not, then they are ready and capable to acquire all of those things and get the same result. If you are having to become the expert yourself, then what is their role?

Anyway, on the other hand, this is an oddball rig that's hard to find someone to work on, so perhaps the usual rules don't apply. Maybe the solution in this case is going to be a team effort between you and the mechanic to get enough info and resources together to straighten things out. None of this is rocket science by any stretch -- these are extremely simple old engines in the end, they have no booby traps, and they are not haunted. All the mistakes are easily avoidable. You just have to choose to avoid them.

If he is ready to approach the job with patience, start over from the very beginning, and follow the service instructions down to the last letter with no shortcuts or "improvements" -- probably with you providing a second set of eyes and helping make sure no steps are missed or altered or skipped -- then he/you will succeed, no problem.

Quote:
Originally Posted by Sethsquatch View Post
So that being said, obviously there's special tools for the crankshaft in addition to the injection pump. Where do I find these?
Is there an alternative that can be used?
How do you even measure 350 lbs on the nut?
That's right. Check out our D24 Special Tools sticky thread for a review of what all the tools are and what they do: https://d24t.com/showthread.php?t=1299

Then, check out our Tool Rental section on the forum, here: https://d24t.com/forumdisplay.php?f=25

Refer to the "Master List" thread in particular. Several members offer the tools for rent or for free loan (with deposit). This would be a little bit of a strange situation for lending tools out -- we are used to sharing tools among us enthusiasts working on our own personal cars, but usually not to professionals using the tools to make money. But, we would find a way to make it happen if you need tools, since the goal of that rental program is to prevent the lack of the equipment from being an obstacle to getting things done. Maybe you would wish to make a charitable donation to the forum for our December hosting fund drive.

One suggestion: in addition to the tools, also get hold of a copy of the Volvo D24T engine "greenbook" (factory service manual) to use as your information reference and your guide for work procedures. Those are also available for loan, but you might want to have a copy of your own. Good condition paper originals are commonly seen for cheap on ebay, books4cars.com, etc, and there are also pdf versions online if you wish.
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  #17  
Old 12-28-2020, 09:57 PM
Sethsquatch Sethsquatch is offline
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Quote:
Originally Posted by v8volvo View Post
Well, that's not your fault.

The point of bringing a job like this to a professional is it becomes THEIR job to have this kind of knowledge, so that you don't have to. Right? You pay them, rather than doing it yourself, because 1) they already possess the expertise, resources, and equipment needed to do the work successfully and professionally, or 2) if not, then they are ready and capable to acquire all of those things and get the same result. If you are having to become the expert yourself, then what is their role?

Anyway, on the other hand, this is an oddball rig that's hard to find someone to work on, so perhaps the usual rules don't apply. Maybe the solution in this case is going to be a team effort between you and the mechanic to get enough info and resources together to straighten things out. None of this is rocket science by any stretch -- these are extremely simple old engines in the end, they have no booby traps, and they are not haunted. All the mistakes are easily avoidable. You just have to choose to avoid them.
In his defense, he knew this was an oddball rig and took it on with full disclosure that he'd be figuring it out as he went. He did an extensive amount of work, and didn't charge me a dime for storage while it was in his shop for 5 months as we diagnosed problems, waited on parts from UK, consulted with mechanics from the UK, etc.

The Pinz did come with full service manual that includes step by step on basically everything, not sure if the Volvo book would be different...?

OK it looks like from the 3 people on the tool rental sticky that v8volvo has what I need unless I'm mistaken.

Also, I'm always happy to donate to sites like this! Just let me know how and when!

Last edited by Sethsquatch; 12-28-2020 at 09:59 PM. Reason: Forgot sentence
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  #18  
Old 12-29-2020, 07:04 AM
v8volvo v8volvo is offline
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No doubt your fellow is a good guy, it's just surprising that he would want to get into deep water on this without being sure he could get out. If I were in his shoes, I would not have agreed to take a functional piece of equipment apart until I knew I had all the resources and ability needed to get it back together successfully. That is basic logic even for the do it yourselfer at home, let alone a professional with their reputation and someone else's property at stake.

Anyway not attacking him personally at all, just confused by the decisions.

The Volvo manuals have good clear procedures that will get you a good running engine in the end if you follow them step by step. We don't know what the Pinz books look like, but it sounds like there was a lot of difficulty getting through the timing process, needing to call overseas, etc. Maybe the instructions have been part of the problem.

The Volvo books also will give you the Volvo tool numbers and part numbers in certain places which might help you figure out what equipment you need more easily. Do the Pinz books reference Volvo tool numbers or do they suggest their own versions?

I believe Volvoist also still offers the full set of tools for rent although he is not on here as often. Others have individual tools though mostly not complete sets. If you would like to borrow any tools from me, just send a PM and we'll work it out.
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  #19  
Old 12-29-2020, 12:05 PM
jetfiremuck jetfiremuck is offline
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I ordered the crafter vw timing tool kit when I replaced my timing belt. I cut a slot in the crank tool in the kit with a 41/2" angle grinder to match the slot in the crankto hold the damper pulley. Worked great.
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  #20  
Old 12-29-2020, 12:30 PM
ngoma ngoma is offline
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Quote:
Originally Posted by Sethsquatch View Post
The Pinz did come with full service manual that includes step by step on basically everything, not sure if the Volvo book would be different...?
If that is the case, then I wonder why are you encountering so many problems? Five months? Continual conferences with the UK? Unless the Pinz manual has incorrect info or perhaps the mechanic is not following to the letter? (I am not blaming, have no proof of this, but we have to admit it is a possibility.)

This may be an important factor in this situation, as it has been in other similar situations:

For sure, this engine requires a few "oddball" maintenance actions. NOT common in passenger vehicle wrenching. NOT even in less-common diesel engine wrenching. Without direct experience on this particular engine, an otherwise "experienced" mechanic is mightily tempted to "make do" with what logically appears to be a "good enough approximation" that seems like it should work, and that has always worked in the past. Sometimes referred to as "Best Practice."

Look at v8volvo's example above about the required >350 ft. lbs. torque spec for the crankshaft pulley bolt. An "experienced mechanic" has likely never encountered this before, lacks the special tools to achieve this high torque spec, lacks any way to correctly achieve this torque setting, has never had to tighten a bolt that tight ever. ALL the other crank pulley bolts he has done before have never given any problems when he tightened them to far less so why not just "do it up like all the others" here?

But with this engine, the result is almost always guaranteed to be slipped camshaft timing ==> valves/piston impact ==> broken valves/pistons/camshaft/bent rods/bent crankshaft, etc. = destroyed engine. THIS FORUM has several such histories here.

I, for one, am feeling our best timely help is being impeded because of the "Telephone Game" we are dealing with here. Something is getting lost in the translation between your mechanic, thru you, to us, and vice-versa. Might be time for you to request you mechanic enter into this thread directly instead of relying on what you can relay to us, remembering, as you clearly stated in your initial post: "This is obviously not my area of expertise."

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