Distributor for gm tbi

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toothofwar
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Distributor for gm tbi

Postby toothofwar » Mon Mar 19, 2018 11:16 am

So I'm in the process of installing a gm tbi onto my 79 cherokee 360. I would live to drop a gm style distributor into it. One that is already locked and has the coil and control module already in the cap. This way all I have to do is plug my 4 pin connector into it from the gm ecm and food it a switched hot. I wired in what came originally with the kit and I think I made a mistake and fried my ecm. So while I am tracking one down that I can put my pre programmed prom in, I'm looking to simplify the wiring with the coil/distributor. Any thoughts?

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toothofwar
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Re: Distributor for gm tbi

Postby toothofwar » Mon Mar 19, 2018 11:19 am

toothofwar wrote:So I'm in the process of installing a gm tbi onto my 79 cherokee 360. I would live to drop a gm style distributor into it. One that is already locked and has the coil and control module already in the cap. This way all I have to do is plug my 4 pin connector into it from the gm ecm and food it a switched hot. I wired in what came originally with the kit and I think I made a mistake and fried my ecm. So while I am tracking one down that I can put my pre programmed prom in, I'm looking to simplify the wiring with the coil/distributor. Any thoughts?

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Also, here is some photos of the progress and how I done it. Nothing is prettied up yet so please be kind on the criticism lol.ImageImageImageImage

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toothofwar
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Re: Distributor for gm tbi

Postby toothofwar » Mon Mar 19, 2018 11:23 am

toothofwar wrote:
toothofwar wrote:So I'm in the process of installing a gm tbi onto my 79 cherokee 360. I would live to drop a gm style distributor into it. One that is already locked and has the coil and control module already in the cap. This way all I have to do is plug my 4 pin connector into it from the gm ecm and food it a switched hot. I wired in what came originally with the kit and I think I made a mistake and fried my ecm. So while I am tracking one down that I can put my pre programmed prom in, I'm looking to simplify the wiring with the coil/distributor. Any thoughts?

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Also, here is some photos of the progress and how I done it. Nothing is prettied up yet so please be kind on the criticism lol.ImageImageImageImage

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Also here is how I wired in the stuff I have now. I pulled the control module and coil from a 94 gm 1500. I will get pictures later today if those mounts.
Image

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FSJ Guy
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Re: Distributor for gm tbi

Postby FSJ Guy » Mon Mar 19, 2018 12:51 pm

Use your stock distributor. The pickup that triggers the duraspark modue will also trigger the GM module.

Use the wiring diagram you posted with the ignition module shown. The ignition module (MUST use a hearsink!!) will give you timing control as well. No need for expensive "HEI" distributors.

Just lock your factory distributor with a quick weld.

See my website for details. Look in the TBI section, IIRC.
Ethan Brady

http://www.bigscaryjeep.com

1987 Grand Wagoneer. Slightly longer than stock.

toothofwar
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Re: Distributor for gm tbi

Postby toothofwar » Thu Mar 22, 2018 9:56 pm

Ok...so update on the nightmare situation on the Tbi..

I had stripped the distributor and cam gear as mentioned previously. So I had replaced with a matched set. Replaced the distributor and hit it again. Started up and purred like a kitten for about a minute. Then died and no spark or fuel spray. Pulled the dizzy out to find my matched set of gears shredded. So now I'm in the process of locking my old dizzy and ordering new gears and gasket kits again
..... anyone got an idea why it is eating gears so bad? The motor has less than 3k miles on a fresh rebuild.

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FSJ Guy
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Re: Distributor for gm tbi

Postby FSJ Guy » Fri Mar 23, 2018 4:33 pm

Sounds like the alignment is off somehow on the distributor.

Are you using the factory timing chain cover or is it a repro? Supposedly some repros were not lined up well. Was there oil on the shredded dizzy gears? I'm wondering if the oiling channel was blocked.

Did you replace the timing chain set when you had the cover off the last time?
Ethan Brady

http://www.bigscaryjeep.com

1987 Grand Wagoneer. Slightly longer than stock.

toothofwar
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Re: Distributor for gm tbi

Postby toothofwar » Sat Mar 24, 2018 10:39 am

The cover is original. There was a little oil on the gears but not much. The timing set was replaced with the rebuild about 7k miles ago. I checked the chain slack when I had the cover off last and it was still good and tight. I think the problem started with the dizzy that came with the kit. It was second hand and I think it might have a bent shaft at how it was locked out from the factory might be messed up. I have took apart one of my old dizzy's and I know how to lock them myself now (got to love YouTube) . So I will be ordering a plain stock dizzy with my next gear set and gaskets to have everything new, not just new to me.

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babywag
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Re: Distributor for gm tbi

Postby babywag » Sat Mar 24, 2018 8:05 pm

I’d be looking @ timing gear oil slot since it’s fresh timing set.
Very common for it be in wrong place or not go all way through.
Deprives gears of oil unless checked/corrected.
Distributor & cam gear chewage probably due to that?

Also move the CTS from tstat housing to intake, very little flow until warmed up there. Engine temp will be out if sync. until tstat opens where you have it.
-Tony
'88 GW (aka Babywag) '90 GW (aka JunkBucket) both fuel injected.

FSJ Guy
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Re: Distributor for gm tbi

Postby FSJ Guy » Sun Mar 25, 2018 12:19 pm

X2 what he said!
Ethan Brady

http://www.bigscaryjeep.com

1987 Grand Wagoneer. Slightly longer than stock.

toothofwar
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Re: Distributor for gm tbi

Postby toothofwar » Mon Apr 09, 2018 8:08 pm

Ok, so it's been a while since I updated. I finally got to order a new set of gears. I was going to order a new dizzy also, but desided I have 3 already, so really no need for a 4th one. I did order a new pickup though. Figured I'd try to make everything as new as possible. I'll break everything else into a couple of posts. First I had to open the dizzy up that came with the tbi kit. Just to see if it was the culprit on the gear chewage. Sure enough I found problem number 1. Broke welds. No wander I couldn't time it, also, there was no washer on the bottom so the whole shaft moved nearly an 8th inch vertically. So I fully disassembled it. ImageImage

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toothofwar
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Re: Distributor for gm tbi

Postby toothofwar » Mon Apr 09, 2018 8:32 pm

Up next I was ready to build the dizzy while my 12 yo son started the fun job of draining fluids and removing hoses and belts to start the disassembly of the front of the motor. So I pull out the gear set and all looks good. However when I tried to install the gear on the shaft, the holes was just a tad off. Well on the 2 original ones it was half a hole off on one side. So I went back to the welded one. By the way, has anyone had any trouble with the crown auto hear sets? I have one of their chains in my transfer case. Been good so far. Anyways, back to the welded dizzy. So I know I'm not as good of a welder as I need to be, so I took the heavy springs from 2 different ones and put the on without the counterweights has anyone done this before? Will it hold up to the inertia? ImageImageImage

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babywag
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Re: Distributor for gm tbi

Postby babywag » Wed Apr 11, 2018 7:52 am

Yes, the springs should hold it.
On distributor gear, if it doesn’t fit properly don’t use it.
You’re already tearing it down to replace them, why risk having to do it all over again?
If they cannot get a hole drilled properly I suspect QC is lacking on actual gear(s) as well.

Get a good used OEM set, or maybe MSD set. Personally I have always used originals and never had a failure/problem. Even mixing ones from different engines. Searching you will find many folks that have had problems with new gears or aftermarket distributors.
-Tony
'88 GW (aka Babywag) '90 GW (aka JunkBucket) both fuel injected.

FSJ Guy
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Re: Distributor for gm tbi

Postby FSJ Guy » Wed Apr 11, 2018 7:10 pm

You don't have to be an expert welder. I just zap it enough to put a bead down to hold it in place. I do it on both (opposite) sides with the idea that it is better balanced that way.
Ethan Brady

http://www.bigscaryjeep.com

1987 Grand Wagoneer. Slightly longer than stock.

toothofwar
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Re: Distributor for gm tbi

Postby toothofwar » Wed Apr 11, 2018 7:27 pm

Some of the carnage I found today...... this thing is killing me.... I finally figured out what jeep stands for. Just Empty Every Pocket!ImageImageImageImage

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babywag
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Re: Distributor for gm tbi

Postby babywag » Wed Apr 11, 2018 8:24 pm

That looks BONE dry, should be oil all over everything.
I’d venture a guess cam sprocket slot is misaligned or not allowing oil all way through.
Lack of oil to gears = massive chewage.

With that amount of metal shavings I’d be @ minimum dropping pan and removing pickup for cleaning.
That is a LOT of metal!
-Tony
'88 GW (aka Babywag) '90 GW (aka JunkBucket) both fuel injected.

toothofwar
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Re: Distributor for gm tbi

Postby toothofwar » Wed Apr 11, 2018 8:59 pm

Yeah. I dropped pan, cleaned everything with carb cleaner, and wiped dry. I popped the timing cover back on and took an old dizzy and converted it to an oil pump primer. After I had it primed I let the drill spin for at least 3 or 4 minutes and not a drop of oil on anything inside of the timing cover. So now what do I do........ where does the oil normally come from in there? I looked all over the cam and crank shafts to see if there was an oil jacket on them, but I didn't see any.

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babywag
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Re: Distributor for gm tbi

Postby babywag » Wed Apr 11, 2018 9:15 pm

Oil comes from cam timing gear, there is a slot to allow oil out to lube everything.
Been an issue for many years that aftermarket doesn’t machine properly.
When gear slot is wrong, you see the result.
Need to remove the timing set and check/fix the oil slot.

sc/397 has good info on ifsja.org
http://www.ifsja.org/forums/vb/showthread.php?t=183822
-Tony
'88 GW (aka Babywag) '90 GW (aka JunkBucket) both fuel injected.

toothofwar
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Re: Distributor for gm tbi

Postby toothofwar » Fri Apr 13, 2018 3:18 pm

Ok, so more in depth today. Took the timing cover off again. I had placed it back on then chucked up part of an old dizzy in a cordless drill and made a makeshift oil primer. After about a 3 minute run, I pulled it back out and the gears was dry. So now I have the timing set out and I'm trying to see what needs to be modified to get the oiling right. ImageImageImageImage

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letank
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Re: Distributor for gm tbi

Postby letank » Fri Apr 13, 2018 5:31 pm

the oil transfer slot has to be aligned with the one on the cam

Image

so do as pictured, and if off, file a new hole in your timing gear

let me come back and find another pict, below is aftermarket, check the shape of the groove

Image

and this is almost OEM, probably...

Image

still missing the pict of interest... the original post used photobucket... so it is gone... but I have it somewhere

not this but it gives an idea

viewtopic.php?f=10&t=12192

Image

Found it, the image is skewed, but this pict shows the offset of the hole

Image

and this one the way to open up the gear to get the oiling channel opened

Image

and the other side, as shown different mods of manufacturer not understanding the problem have added more slots, the OEM has no slots, a bit of a chamfren, it is the bottom one, you can see the chunks of the plastic cover/caps that are still present on the cogs, it was on the earlier set of timing gears

Image

I do not have a pict of the front of the cam
Michel
74 wag (349 Kmiles... parked, next step is a rust free body)
85 Gwag (225 Kmiles... the running test lab)
See Engine bits and Fuel and brake lines, and Body work

toothofwar
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Re: Distributor for gm tbi

Postby toothofwar » Fri Apr 13, 2018 7:10 pm

So pics will come tomorrow as I can barely see straight. So I wanted a side by side comparison of some timing sets, so I pulled the set from my spare motor. When I held them side by side, I started noticing a lot of changes. The new set was made in Japan and was ( these are just guesses on the measurements. I didn't pull my tape out.) About 1/2" wide, but the spare set was made in good ol USA and was about 5/8" or better wide.so just for poops and giggles, I put that set on and mocked the cover on. When I looked down the dizzy hole , the cam gear was now dead center now. So how can there be 2 different widths of chains? Anyways my gasket kits won't be here till in the morning so I pulled the oil pan back off and found more metal, so I am flushing everything a few times to try to get it all out. I think I need to move this to general discussion cause this project has went from am tbi install to an almost full rebuild.....

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