Weird problem with the IP timing

[mihkel]

It started out after I took the pump off and changed the main shaft seal. In the beginning I managed to somehow time the pump 180 degrees off, so it was running really bad and rough. After sorting that out I could not time the pump properly anymore. I have done it a few times before so I know the procedure and have not had any problems what so ever before.

The problem:

I aligned the marks on the pump case, the pump bracket and pump sprocket and then the one on the flywheel (I even checked if the flywheel mark was the right one, as there are two of them). I put the dial gauge in and rotated the engine backwards to find the lowest reading. To my amazement I had to rotate the engine backwards a bit too much. The dial stopped at about 5-6mm. Double-checked everything just to be sure, rotated the engine a few times but still the same. Tried approaching it in different ways but still the same. Out of frustration and as I was running out of time I set the pump just by ear.

Have driven it for a few months like that, mpg is great and no problems with power but cold start is a bit difficult. So today I decided to give it another try. Looked at the videos and read about the timing procedure. I did everything the same way but still no success. If I set it with the dial, then it is way off - it starts rough and smokes like hell I guess it is about 5-6mm on the gauge. I align the marks, put the dial in, rotate the engine backwards but the dial does not stop until 5 or 6mm. Have not seen this thing before.

Only thing that I could think about was the plunger being sticky. So I ran pure 2 stroke oil through the pump. Still no difference. And yet again I finished with timing it by ear.

Any ideas?

[anders]

You can't get a zero reading on the plunger? Your dial indicator should be adjustable so you can get a "zero" reading when the plunger is fully seated. Adjust to .9mm at TDC without cold start hooked up. I have adjusted several D24's and D24T's it seems each one likes to have a different advancement. Some like .7mm and some like 1.00mm.

[mihkel]

The problem is not with the indicator, it works fine and is used correctly. The plunger itself does not seem to stop. When I start going back with the engine the reading on the dial decreases steadily but bottoms out at about 6mm. Should stop between 0.5 - 1.5 but does not (as the engine is running ok that should be the real reading)

[anders]

What is the lowest measurement you get? what's the highest you get? While rotating the pump. I'm assuming you are putting a 1 or 2 mm pre-load on the dial.

[mihkel]

Originally Posted by anders

What is the lowest measurement you get? what's the highest you get? While rotating the pump. I'm assuming you are putting a 1 or 2 mm pre-load on the dial.

Have not checked the highest and lowest yet. When I set the pre-load at 2mm, the dial itself bottoms out, so I have had to set it higher, but that is not the case. There is something going on with the pump? And again, the engine is running ok. It is a D24 egine with a D24T pump + turbo, I have had no troubles with the power or running. I have set the timing before exactly the same way, but this time it is going wrong some how ... really really weird.

[v8volvo]

What's the range of your dial? I use one that reads 0-25mm and usually set it with a preload of about 15mm, just because that is where my dial fits best in the tool. The entire stroke of the piston is under 2mm so you should have no trouble reading it. Are you sure your dial is in good shape and not sticky? Sometimes you have to "help" it return to make it follow the motion of the piston and get it zeroed accurately. I also had one time where the rod got bent and was binding up inside the tube which made it read funny.

You also may have better success if you rotate the engine forward only. Sometimes when you take loose the cold start linkage it takes a couple pump rotations for everything to settle back into the warm position where it has to be for an accurate timing setting. (Speaking of which, you DID remember to disengage the cold start linkage before attempting to set timing, right?? If you set it using the dial indicator with the cold advance lever pulled forward, your actual setting will end up way off, about .25mm off, and it will not run well.... easy mistake to make, certainly one that I have made enough times! ) Making sure the cold start is released and then spinning the pump and motor over a few times should get the pump's internals settled, and get you to a point where you can make an accurate setting of timing.

I'm a little confused about your saying measurements like 5 and 6 mm, and by the difficulty with finding a zero point. If you turn the engine over twice, you should see the needle on the dial move from a minimum point to a maximum point, in a roughly sinusoidal pattern, six times during those two crank rotations. The minimum point that it returns to each time is the zero mark. The total displacement should be somewhere in the neighborhood of 2mm or slightly less. Once zeroed, as the engine is turned over by hand, the needle should sweep from your zero mark to its max and then return back to zero each time. There's no way for it to move the dial 5+ mm, so if you are reading a displacement like that then either your dial tool has something far wrong with it or there is some mistake in your method that we are missing.

Regardless, bottom line is if it runs, then there can't really be anything wrong with the pump, and if there's not anything wrong with the pump, then setting it by the spec using the tools should result in the engine running properly. If you're only able to get it set by ear and doing it using the dial keeps giving you a bad result, then it has to be some kind of glitch with your tools or your procedure that's causing the discrepancy. Should be something simple. We'll find it...

[mihkel]

It is a pretty new dial, have used it only for the pump timing, it's some German made dial with a 10mm range. I have set the timing once with the dial with no problems. Before that I used some kind of Soviet made dial which has seen it's days!

There's no problem with the cold start lever as I've ditched the original system and it's completely manual controlled by a lever from the inside. So the lever is loose all times when it's not pulled from inside the car.

The dial pattern that you are describing makes sense to me as well. That's why I'm really confused with the reading that I get. Lets say that if I pre-load the dial at 10mm and turn the engine back, the needle doesn't stop until 5 or so mm.

Well, I'm going to try it again with the other old dial and then again turning the engine forward only. Turning it forward only I should find the highest reading just before the TDC mark and zero the dial there and then proceed turning it to the TDC.

[mihkel]

I feel bloody stupid now ... The newer dial that I was using turned to be on closer inspection a 0-1mm range. That's why I was getting the "6mm" reading, which is actually 0,6. Anyways, Tried the other older dial and got the reading of 0.7mm (must have missed one turn with the other gauge). Timed it to 1.00mm and it runs like a charm!

But I'm still happy, got a great lesson Now I know better how the pump actually works and try to be more careful with the tools that I'm using. I was really sure that it was the right one, had no clue what so ever, as my dad had bought it for the same job but had never used it.

Thanks guys!

A little video of how its running now

http://www.youtube.com/watch?v=WkYarAKBQLM

[v8volvo]

Glad you got it sorted out. Sounds healthy! Love the flag motif on the valve cover... the Germans who designed that engine might not be as happy, though.

Where are you located? Your 240 looks like a US model judging from the headlights and the big bumpers, but the license plate looks like an EU plate in a US profile. And I see what looks like a SEAT or a Renault parked next to it as well, which means you are certainly not anywhere on our shores.... What's the story?

[mihkel]

Yep, you got pretty close It's in Europe, Estonia. And indeed, it's a Seat Altea next to it.

Yeah, I like the flag! It's really multi-cultural car - Swedish design, German engine and US spec.

Made a thread of the car http://d24t.com/showthread.php?t=931