The other day I started a thread about water/ methanol injection systems. No-one really new very much about it, and the thread quickly deteriorated into a timing thread. There were some member who said that road timing an idi was totally acceptable, and others that swore by the Ferret pulse timing method.
Well......being one of those people that go by the " if it ain't broke, don't fix it " theory, I have stuck my head in the sand for the last 20 years. I have put up with 9-10 mpg, a huge flat spot on acceleration, and clouds of black smoke under load. After reading the comments on the previous thread, I decided to address the situation. I removed the idle-up solenoid, the ATS turbo air box, and the throttle cable w/cruise control cable. I thinned down a 9/16 short box wrench on the grinder, and loosened the IP. Next I got my largest set of channel locks, and advanced the timing 1/4 of an inch from where it was. Put everything together, started it up and............. Too much, too much advance ! The engine let me know
what it thought about what I had done, the second that I stepped on the pedal. Back to the garage. I then retarded the timing by exactly 1/16 of an inch, put it all back together, and wow! Great acceleration, no access diesel clatter. In addition, it seems to shift much smoother. I'm now hoping that my milage will increase. Macrobb was right. There is absolutely no reason to be afraid to road time an idi. It's a pain in the ***, but well worth the effort. Sorry that this is so long, but this was way better than arguing about the method used to set timing on these trucks.👍

 

Glad it's performing better, and I hope it doesn't grenade within a few thousand miles. Let us know how your glow plugs and rod bearings are doing after you work the truck for some time. Also let us know what your timing is set to if you ever bother to check it.

I don't understand the fear of doing a timing job properly. Don't fool yourself into thinking you set the timing, you have no idea where it was and no idea where it is. You adjusted the timing to something more advanced than what it was. Hopefully it's in the safe range.

 

Where the timing was, is just as unimportant as where it is now. I advanced it to the point of un-acceptability for my engine. I then backed it down to a point that is optimal for my engine. The fact that it starts well and runs well tells me that the timing is within a range that is certainly better than it was for the last 20 years.

 

You could say the same thing about a gas engine and be blissfully ignorant of detonation, inefficiency, and hammering your rod bearings. My 460 runs like a raped ape with 16* initial timing and 36* by 2000 RPM, but if I kept it there the engine would be toast in short order. It detonated on 94 octane and certainly does on the **** 93 that's available now. If I advanced until obviously too much then backed off until the engine seemed to "start and run well" it wouldn't have survived 1000 miles without catastrophic failure.

You're just winging it, hopefully it's set in an acceptable range and it works out. It's a very real possibility it's not and you'll be crying about rebuilding your IDI a few thousand miles down the road. The fact that you mentioned advancing the timing 3/16" on the pump to timing gear cover flange indicated the timing was extremely retarded previously or excessively advanced now.

By all means just wing it and risk damaging your engine being completely unaware of the timing curve but please don't encourage other people who may not understand the risks to do the same.

 

All of the IDIs I've bought have been excessively retarded except for the one that had had a new pump recently... Of course, considering my budget, there might be a relationship there...

Anyway, I honestly doubt advanced timing will kill an IDI. It's not a gasser - Diesel engines pretty much detonate constantly anyway!

I'm still unsure about advanced timing killing glow plugs... but I don't leave my timing advanced(to my feel), and what I *do* run, doesn't seem to kill glow plugs.

I mean... I'm still running a set of 7 Champions in my '93, 6 of which were there when I bought it(8th is a Motorcraft I recently installed). Everyone says that Champions are junk, but erm, they still are working for me. And the one that died? Came out with no deforming at all.

 

I'm not sure if the 83-86 glow plugs differ from 87-94 glowplugs but I could never keep a set in my truck for more than six months. I changed everything and set them up manual and it never took more than 6 seconds in 20 degree weather to start it.

I never had problems with them when my pump wasn't turned up or advanced, if they are the same internally, which I doubt because everyone I know with a 7.3 gets five years out of a set. It could have been my timing or just the crazy egts but either way ether start solved my problem and the cost of ether is cheap enough it would be like buying a set of glows every six years.

I doubt timing can kill rod bearings in an idi. Or a gasser for that matter. I could see a hole in a piston on a gasser but never a rod.