M21 timing belt questions

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gadget73
Posts: 1247
Joined: Nov 22, 2017 10:30 PM
Location: New Jersey

M21 timing belt questions

Post by gadget73 »

Greetings
Next week I will be picking up a 1984 Lincoln Continental with the M21 turbo diesel in it. Among the things I plan to do is replacing the timing belt. The car hasn't been tagged in 10 years and the current owner has no idea when the belt may have been changed last. He has only owned it a few months and has never tagged it. It is currently running and I'd like to keep it that way.

Looking around for parts, I find several brands listed at pelicanparts: a Febi for $25, a Continental for $39 and a BMW for $108. Do I really need the genuine BMW belt, or are the aftermarket ones good? Any preferences? I've honestly never owned a car that used a belt before so I have zero experience here.

While I'm in the area, are there other items that should be changed? I was thinking water pump, timing belt tensioner, valve cover gasket, the timing cover seal, and probably the thermostat and any water hoses that need to be unhooked. Same questions there about brand, the BMW genuine stuff is considerably more expensive. I will buy it if it truly is that much better but I don't want to waste my money here either. I do plan to check the valve lash while I'm in the area.

Does anyone have a mechanical drawing of the cam locking tool, or even just a good picture of one actually on the engine? I'm curious if I can fabricate this tool myself. They're pretty expensive. I *might* have a lead on where I can borrow one but if that falls through I'd like to explore other options. I plan to make the pump and crank lock pins on my lathe.


If anyone has advice for someone who knows virtually nothing about this engine, please feel free to let me know. I've got Lincoln experience, but I have no diesel experience of any sort. Thanks for any wisdom that you fine folks can share.
noddaduma
Posts: 28
Joined: May 19, 2017 2:09 PM
Location: Brookline, NH

Re: M21 timing belt questions

Post by noddaduma »

Do what most of us do and mark the positions of the cam pulley with white-out or paint before you take the old belt off. Turn to TDC before marking position and insert locking pins to keep the diesel pump and crankshaft from rotating. Don't sweat it too much...It's still not rocket science with a cam belt.

Search the forum here and you'll find lots of discussion on this. There's literally a thread 6 posts down asking the same question with the same answer, so you'll likely find an answer to every question you might have with a search. Not that you can't post to ask, but you might get an answer quicker with a search. :)

The aftermarket belts will work fine (My belt is a Continental).

Good luck!
gadget73
Posts: 1247
Joined: Nov 22, 2017 10:30 PM
Location: New Jersey

Re: M21 timing belt questions

Post by gadget73 »

Thanks for confirming an aftermarket belt won't be instant death. Any idea on the tensioner or water pump? Non-OE ones any good or stay far away? Mostly thats really what I need to know. I hadn't been able to find solid confirmation about what brands, just some mention of "Conti", which I took to mean Continental ?

I had seen other threads mentioning how to do it without the cam lock, I was just curious what the tool actually engaged on though since I hadn't seen pictures. I found a picture of the cam somewhere and now I understand. It has a square piece on there for the tool to engage. I'm guessing pics of what I was asking probably existed but a lot of threads have dead Photobucket images now.
Kopek130
Posts: 42
Joined: Aug 03, 2016 7:32 PM
Location: Fairfax VA

Re: M21 timing belt questions

Post by Kopek130 »

Timing Belt is continental. That's what I got.

Go to BavAuto and you can get a off brand water pump that's what I'm using.

Also get a lower temp 71C thermostat.

Next is make sure the fan clutch is good. Engine temp will rise. If getting a new one specifically look for SACHS it opens slightly lower than Behr.
Kopek130
Posts: 42
Joined: Aug 03, 2016 7:32 PM
Location: Fairfax VA

Re: M21 timing belt questions

Post by Kopek130 »

As for timing yes there is a whole process but just count the teeth and swap it over worry about exact timing later.

If I am not mistaken, I don't think the Lincoln uses the Bosch VE pump. If you could take pictures of your pump that would be cool.
gadget73
Posts: 1247
Joined: Nov 22, 2017 10:30 PM
Location: New Jersey

Re: M21 timing belt questions

Post by gadget73 »

Much appreciated for the recommendations. Is the cooler thermostat a reliability thing?

I pick the car up next weekend, I'll post pics once its in my driveway. Just trying to do a little planning while I don't have something here to wrench on.
noddaduma
Posts: 28
Joined: May 19, 2017 2:09 PM
Location: Brookline, NH

Re: M21 timing belt questions

Post by noddaduma »

The Lincoln uses the VE Injector Pump.
gadget73
Posts: 1247
Joined: Nov 22, 2017 10:30 PM
Location: New Jersey

Re: M21 timing belt questions

Post by gadget73 »

Depends where it was sold. 49 state got the VE, the California model got a VP-20 according to one of the pieces of Ford literature linked up above. I'm not sure whether this is a Cali car or not. I doubt it but anything is possible. Its currently in New York, but it came north from Texas. Where it came from before that, no idea.

I guess on the subject of that, in the sticky up above where it talks about the injector pump static timing, is that for the VE or a different pump? The Ford literature gives different settings for the VE and the VP-20. They actually apparently don't like to talk about VE static timing, but they give it as 0.65mm +/- 0.02mm for the VP-20 and 0.63mm +/- 0.04mm for the VE. Handily they also give that in inches, all my dial gauges are inch.
offroadkarter
Posts: 557
Joined: Nov 03, 2014 1:00 PM
Location: Lehigh Valley, PA

Re: M21 timing belt questions

Post by offroadkarter »

So you picked up Zach's car? I helped cut and buff that thing back in September when I was over his house.

Image


What are your plans for this thing, keep it stock? I was looking to help Zach do a manual swap in this thing.
gadget73
Posts: 1247
Joined: Nov 22, 2017 10:30 PM
Location: New Jersey

Re: M21 timing belt questions

Post by gadget73 »

yep, thats the one. Got it home yesterday afternoon.

Keep it fairly stock is the plan. For the moment I just want to fix what I know ails it and go from there, so its all the boring maintenance garbage for now. Got the odometer working last night, tonight will be accessory belts so it will actually charge. The alternator belt looked like a rubber band, then it just quit entirely. That one drives the water pump so kind of important.
offroadkarter
Posts: 557
Joined: Nov 03, 2014 1:00 PM
Location: Lehigh Valley, PA

Re: M21 timing belt questions

Post by offroadkarter »

Yeah those belts on it were pretty crap, I'm surprised they lasted as long as they did.

Also if you haven't already, you should read up on "what not to do with a ZF 4HP22 4spd" IE: Don't rev it in neutral after it's been in drive. Too much and you'll lose all forward speeds.
Last edited by offroadkarter on Dec 07, 2017 9:23 PM, edited 1 time in total.
gadget73
Posts: 1247
Joined: Nov 22, 2017 10:30 PM
Location: New Jersey

Re: M21 timing belt questions

Post by gadget73 »

Thanks for that. Always useful to know whats going to blow up a probably very expensive part. I don't tend to rev the crap out of things in neutral anyway.

You guys did a good job with the detailing, it looks pretty decent despite the shot clearcoat.

yeah the belts were shot. It needs a tensioner too, which I can't find. Apparently it can be disassembled though so thats on the list. They don't fit in there too good, the serp belt has to sneak between the fan and the crank pulley and there is just about enough room for it. That alternator / water pump belt is a feeble thing too, looks like it should be a wider belt or a multi-rib. No way to do it unfortunately.
offroadkarter
Posts: 557
Joined: Nov 03, 2014 1:00 PM
Location: Lehigh Valley, PA

Re: M21 timing belt questions

Post by offroadkarter »

gadget73 wrote:Thanks for that. Always useful to know whats going to blow up a probably very expensive part. I don't tend to rev the crap out of things in neutral anyway.

You guys did a good job with the detailing, it looks pretty decent despite the shot clearcoat.

yeah the belts were shot. It needs a tensioner too, which I can't find. Apparently it can be disassembled though so thats on the list. They don't fit in there too good, the serp belt has to sneak between the fan and the crank pulley and there is just about enough room for it. That alternator / water pump belt is a feeble thing too, looks like it should be a wider belt or a multi-rib. No way to do it unfortunately.

Not sure if you've come across it yet, but realoem is the site we use to look up parts. It's pretty much a carbon copy of the BMW NA dealer parts catalog

https://www.realoem.com/bmw/enUS/select

You'd probably want to look up 84 or 85 e28 524td
gadget73
Posts: 1247
Joined: Nov 22, 2017 10:30 PM
Location: New Jersey

Re: M21 timing belt questions

Post by gadget73 »

Bookmarked. Finally a site with pics to go with the parts. Half the battle is figuring out what to call a specific part.

Its very much the BMW aspect of this car that I'm not real familiar with. Between the 86 Towncar and the 91 Mark VII, I get the Ford factor. I also get the lack of Ford support for older stuff so I'm glad that BMW seems to have better support.
uturn
Posts: 19
Joined: Nov 22, 2014 6:07 PM

Re: M21 timing belt questions

Post by uturn »

Go with the factory rated temp for the thermostat, the computer might try to compensate if it's not getting to temp and might create other problems.
The tranny issue- there's a delrin seal kit to fix it.
gadget73
Posts: 1247
Joined: Nov 22, 2017 10:30 PM
Location: New Jersey

Re: M21 timing belt questions

Post by gadget73 »

Does this actually have a computer? It runs the VE-20 pump, no timing control. I'm still waiting on a few manuals to show up so I'm not 100% on what is there. I know it has a diag plug, and its supposed to have an injector lift sensor but that is missing. I think someone may have changed injectors at some point and used a standard one instead of the one with the sensor.

Roger on factory temp t-stat. I've always been leery about changing the temperature there unless there is a solid reason. Usually I see the t-stat being changed to try to mask some cooling system problem and it either doesn't work or causes other issues.

Absolutely no desire to get into the transmission though. Fluid and filter changes are as far as I want to go. Nice to know there is a fix if it comes to that. If it dies, I will ask whoever rebuilds it to use the updated parts.
Kopek130
Posts: 42
Joined: Aug 03, 2016 7:32 PM
Location: Fairfax VA

Re: M21 timing belt questions

Post by Kopek130 »

I just had a quick discussion with a bosch diesel shop tech and here's a summary:

1 Fuel going into the pump, gets pressurized via a vane pump, thus providing internal pump pressure, this is before the fuel gets to the plunger to the hard lines into the injector nozzles.

2 Higher RPM will of course increase internal pump pressure. There is an adjustment that can be made to control internal pump max pressure.

3 There is a spring that advances timing as internal pump pressure increases.

THIS IS WHERE THE ELECTRONIC VS MECHANICAL CONFUSION COMES IN

The diesel tech said there's an electronic solenoid that determines how much internal pump pressure is allowed push on the advance spring. He said that if you disconnect #4 socket then you won't have power in higher RPM because of lack of advance (because the advance spring gets no additional pressure). #4 injector and flywheel position according to the ETM go right to the "diesel computer" in the glovebox. But what I cannot find are wires going out of the computer and back out to the pump itself. I'm sure it's right in front of me, just called something different.

All of this could be answered if I look under the pump for wires. All I know from glancing in the engine bay are the following 2 items:
- egr idle switch
- cold start solenoid, which all I see is just "pulls the accelerator lever", not a "cold start advance", "advance" being timing?
gadget73
Posts: 1247
Joined: Nov 22, 2017 10:30 PM
Location: New Jersey

Re: M21 timing belt questions

Post by gadget73 »

Mine appears to be missing the injector lift sensor. There are no wires on #4 that I can find, but I believe I see the plug that should connect to them. I know the tripminder doesn't work, and that is somehow driven off the lift sensor. It tells me its doing more than 100 mpg. Sounds nice, but not realistic.

I may be very wrong here, but my reading says the California model came with a VP-20 pump that has an advance solenoid, and the VE-20 49 state model does not have that solenoid. Maybe the Cali model has computer control and the 49 state does not? Still waiting on a few manuals to confirm that. I have the electrical manual and the engine diagnostics manual that covers injection pump settings and such in it coming.

I actually need to figure out whats with the cold start solenoid too. The cable clamp for it was removed because apparently it got stuck in high idle. Not sure if its just not adjusted right or if that is not actually working. I know it doesn't idle up when cold.
gadget73
Posts: 1247
Joined: Nov 22, 2017 10:30 PM
Location: New Jersey

Re: M21 timing belt questions

Post by gadget73 »

Got the Ford electrical manual, and this is what it has to say about cold start timing advance.

49 state
When the engine coolant temp is below 30C and the ignition switch is in the run position, power floes through the cold start advance temp switch to the cold start advance solenoid on the injection pump. When the cold start advance solenoid is energized the injection pump timing is advanced to provide a smoother running cold engine. When the coolant temp reaches 30C, the temp switch opens, cutting power to the advance solenoid and injection timing returns to normal.

California only
The cold start advance on California only vehicles is controlled by an electronic control assembly located in the luggage compartment. When the engine running, the CA receives inputs from the coolant temp sensor in the cylinder head, the speed and crank position sensor mounted at the lower LH rear of the engine block and the lift sensor on the #4 injector. The control unit monitors these inputs and determines what the injection timing should be. it then sends a variable signal to the control solenoid mounted in the injection pump. this signal controls the position of the solenoid which controls internal pressure in the pump, varying injection timing as necessary.

so apparently both have an advance solenoid, one is controlled by a simple temperature switch, the other has a computer. Pics show the solenoid basically under the throttle lever with the connector end aimed towards the back of the engine. The ECM, if it has one, is a box in the trunk, looks like its mounted to the back of the rear seat.
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