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Engine Specific Info and Questions => IDI Engine => Topic started by: rodpaslow on June 05, 2013, 09:01:34 am
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I've looked back at several posts and most posts have a conversation on on what's been used in the past both 1.9 AAZ and later 1.6 (Canada ME/MF 1V engine codes). What is suggested in the book is .95-1.05 timing with 1.00 ± .02 as the adjusted value. One post asked specifically what's the best value - it was never really answered - specifically best for starting?
If it were a gasser, I'd say slightly retarted. A 1.6 TD deisel -is 1.05 better for starting? Mine is currently set to .97mm
(Just a not the cold start cable advances 5° as stated by bently manual)
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If fogot to mention - if you're not worried about increased noise - simply better starting timing.
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There is no best value. Factors such as the condition of the engine, the condition of the injection pump and some internal settings of the injection pump have an effect on how it runs with different static timing settings. Advancing the timing can overcome some problems associated with a worn pump or low compression. Essentially, no two engines will run the same.
I also don't believe in "time it by ear." I think that's how people end up with timing settings that are way out of line like 0.40 mm.
What I believe in doing is to set it at the best setting (where the engine runs and sounds the best) that is still withing the specified range. I think the the range they specify should be safe for the engine. Try different settings that are within range. You want "clack" when it is cold and noticeably more clack when you pull the advance cable but no clack when it is hot idling in traffic. More advance = more clacking. You want it to start easily and not smoke at idle. Less advance generally = more smoke and harder starting.
Small incremental changes make a big difference, btw. The previous owner had the car set at 0.97. I think it ran like ass, it would smoke and it would misfire on deceleration. The cold start cable didn't seem to make much difference. I bumped it up to 1.02. It's too far advanced and clacks too much. I will probably put it at 1.00. 0.97 is probably too retarded and 1.05 probably too advanced for a TD engine that is in good condition.
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You say you don't like timing it by ear.
Then describe how you time it by ear. :)
Great advice though.
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In my experience, a good engine with a good pump will fire on the first crank as long as it is timed anywhere near the spec'd range.
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I think that will help -thanks all. Just before I took it out commission (changing tranny) it was starting terrible at around the freezing mark (end of April -in Canada). Engine is in good shape, maybe 10,000 km on a new engine so clearances, rings, etc are all fine. Starting terrible meaning after standard glow time - I would crank it for probably half 20-30 seconds before it would start firing and start. 900CC amp battery and relatively new starter. It was turning over quickly just would not catch easily.
I know I had 1 glow plug not working, since then have changed them all and reviewed all items with glow system and all are good at present. I will be starting it tonight, so it should be much, much quicker to start once the injector lines have been bled. (I take the lines off to change g-plugs).
I have done the glow system where I have 4 fuses for each glow plug (like vince's suggestions). Right now they are 20 amp. should they not be higher? Will this restrict the amperage they can draw? Just curious.
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Plugs pull like 9A each.. a 20 is fine ;).
If it still starts like utter crap after you replace the plugs.. I'd try knocking the timing back down actually..
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I tried running with 10 amp ones on each GP and for some reason one of them pops the fuse at the most inconvenient times. So I had to up that one to a 15 and it has been solid working ever since. Ruins the Feng Shui under the hood.
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I'm going to try timing by ear.
To clarify:
1. Warm engine.
2. Loosen 4 bolts
3. Move pump ( can someone clarify which way is advanced) under marble- like sound - then back off a bit.
4. Tighten bolts
Am I missing anything?
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1. Warm engine.
1.1 Mark IP current position.
1.2 Ensure cold-start lever is disengaged.
2. Loosen 4 bolts.
3. Move pump top toward valve cover until clatter increases - then back off a bit.
4. Tighten bolts.
5. Loosen and retighten injector lines at IP to release the torque which can cause stress fractures.
Am I missing anything?
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I started it last night, current temps about +20 to 25° (about 70 to 80°F) and it took right off with new glow plugs. I basically have a new starter in place to with change over to 02A, it took right off. I think I will leave timing as is for the summer and once it's late fall I may test and see if advancing it to 1.00 helps with starting if needed.
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I loosen the lines at the IP, and at the injectors and I loosen the injector line clamps, nice and loose, to allow them to reposition themselves, then re-tighten everything so there should be no stress on anything... But I'm paranoid.
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Thanks for the instructions!
Will adjust this weekend.
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The pump can be hard to turn with the injector lines hooked-up.
I grab one of the accelerator cable mounting bracket bolts with a vice grips to adjust timing with the engine running.
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I don't adjust it running, for some reason it makes me nervous. I've got it adjusted good without it running, just have to start it a couple times, no biggie. And no stress on the lines.
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I think my problem has not been the timing starting it, it look like I screwed with the (90 pump) residual fuel and the book says if that is back off too much it will take a lot of cranking to start, simply because it has to build up fuel pressure inside the pump? I don't know, but mine was backed right off.
So I adjusted it and I can tell the difference when i step on the accelerator, the pump responds much sooner. I didn't have time this morning to re-adjust the idle, it's idling around 1500 rpm warn. I did screw out the idle screw at the back of the pump to get it down, as much as I could, I will back off the fuel screw a bit and see if that will fix it.
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I think my problem has not been the timing starting it, it look like I screwed with the (90 pump) residual fuel and the book says if that is back off too much it will take a lot of cranking to start, simply because it has to build up fuel pressure inside the pump? I don't know, but mine was backed right off.
So I adjusted it and I can tell the difference when i step on the accelerator, the pump responds much sooner. I didn't have time this morning to re-adjust the idle, it's idling around 1500 rpm warn. I did screw out the idle screw at the back of the pump to get it down, as much as I could, I will back off the fuel screw a bit and see if that will fix it.
I had something like that happen with my na pump bottom that I tried to turn into turbo pump with top. Fuel screw didn't reach internals the same so I had to break the collar and start from fresh because stock setting and the car wouldn't even run :)
One tuning I was finally able to get the car to idle and start and I thought I was good by adjusting the idle to the tach. I didn't notice anything was really wrong until I took my rabbit out for a test drive. I got around but once in the street the poor car barely wanted to move its own weight and I couldn't rev it out, etc. Whoops turned around real quick :) Then I slowly brought the fuel screw in until I got the power back I thought I was used to with stock settings.
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Running is way easier and precise. Loosen the bolts so that the force needed to move the pump is a good shove or whack of a mallet (this is what I do).
That way, you can tap tap tap it this or that way depending on how it revs, the sound and how it idles.
The number means nothing.. I have told many this.. I haven't used a dial gauge in nearly two years and have many many many diesels on the road that have been timed by my hands, ears and butt-dyno. Four of which are in my drive-way and are daily driven.
I also don't believe in "time it by ear." I think that's how people end up with timing settings that are way out of line like 0.40 mm.
Hey man, if it runs well at an absurd timing number who are you to say it is wrong? lol.
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Yeah, I think not having a number to go by is dumb. VW spent tons in engineering, but the one thing they could have skipped was the timing procedure??? Nah, even libby has a number with the timing light. If your pump is that worn that you can't get it running well without being in the range of .90-1.10mm send it out and have it redone. Even if you time by ear, I think it dumb not to have a number to go back to if you had to do the timing belt again someday.
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All you old timer Gasoline/Carb guys never turned your distributor without the timing light on there to get the best performance? Have a guy in the seat on the verge of a brake burn and listen for ping?
Haha, The specs are for brand new parts. All of them. compression, injectors and the pump entirely.
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So I know you can go by "seat of pants", but without measuring where do you start. My car warm, has very little to no 'clack', but seems like good power once on boost.(I think its around .97mm) So do you tune it so it has a bit of "clack"? I'm assuming you advance it to get the best "seat of pants" - in my case? If you had too much timing you would go back and retard it.
just as a question - what degree of timing is 1.00? would it be between 5 and 10 BTDC?
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So I know you can go by "seat of pants", but without measuring where do you start.
Wherever gets the engine sounding its best. I start my timing procedure (usually after pulling hte pump or a belt job) with the pump in the middle of its movement. Have a person work the key and throttle if need be to keep it idling and then I have my hand on the pump to adjust from there.
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Thanks, I will give that a try. Last night I advanced it from it's "rest position" where it sat with no hand adjusting and I'm a long way advanced I and if definitely didn't start any better and lost power by quite a bit driving it. I will try a bit retarded from it's resting position and see if that's any better. Thanks for the advice.
I can see why the book is just a starting point, as fuel, pumps, injectors, turbos, etc will have all seem many miles or rebuilt and will not be the same as it was.
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I can see why the book is just a starting point, as fuel, pumps, injectors, turbos, etc will have all seem many miles or rebuilt and will not be the same as it was.
And even then.. it is just a guide line that is rather vague and seemingly loose.
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Timed the ip in 1.6td today. I advanced it a bit . Starts a lot quicker, no white smoke.
Although I wasn't completely sure how loud of a clang\ marbley noise it needs to make, just before I retard it a bit? And what does a well-timed diesel sound like?
Any sound clips?