Converting turbo to carb, revisited.

[Big_P]

Still thinking about doing this on my 600 since I can't seem to come up with an engine harness for it. And I'm not even sure it's the engine harness that's the problem. Friggin' mice. The car's in too good shape to scrap and I highly doubt I could get anyone to buy the shell.


Main concerns at the moment:

The Holley 5220 is for a 2.2 and I'm not sure how it could be jetted to use with a 2.5. It's a turbo 2.5 block with a swirl head decked .050.

I'd have to use an inline low-pressure fuel pump, right?

Could the 1.7 distributor be modified to fit the 2.5 block? To eliminate the need for electronics and use vacuum advance.

Thanks boys and girls.

[shackwrrr]

have you thought abut a trick blow through setup?

[88_pacifica]

Still thinking about doing this on my 600 since I can't seem to come up with an engine harness for it. And I'm not even sure it's the engine harness that's the problem. Friggin' mice.

Do tell...

What are the symptoms? Does it even start? I assume that it WAS/IS a turbo car to start with? Did the mice basically ruin ALL the wiring to where it couldn't even be pieced together?

It seems to me that it would be somewhat easier to try and rebuild the harness than to take out the harness altogether and put a carbed one in it's place. Am I missing something here?

[JDAWG]

really i would choose fuel injection over carb any day, just trace some wires for continuity, never understood why dumb rednecks would rip out fuel injection and put a carb on their V8s, well I know why cause they cant figure out what 5 sensors do. But why rip out a billion dollars of R&D and throw on 40 year old technology?

[Big_P]

----! I just made a nice long post and it got deleted.

Here we go again.

It ran great. I holed a piston and it sat for 9 months. When I built a new motor with extra goodies (+20's, ported head, rebuilt 2.5, rebuilt 413 ,3bar map, custom cal) and put it in I was having weird electrical problems. It would run for one second, then I'd hear the ASD "click" and the engine would shut off. The only way it would restart was if I disconnected the battery and reconnected. Then it would run for a second, die all over again. I traced everything. I had pinouts to the LM and PM, I made sure all ground were good, all voltage was where it needed to be, tested the ASD, etc. All fine. I disconnected the alternator harness and it ran! Then I reconnected the alternator harness and it still started and ran fine. I drove it for one mile and it started smoking like crazy. Looks like the good used TII turbo I bought had a seal go bad from sitting. I was taking a video of it and then it died at idle.



This is the video.

I now have 12v when cranking at BOTH of the coil wires. What the ----? Tried another LM too just for kicks.

Datastream with the Genisys and Snap-On "brick" give me WILD sensor readings. 2.55v across the board on everything. Key on Engine off, it says it's turning 4067 RPM.


This isn't meant to be a redneck thing. I'm an ASE master, I know what I'm doing, I just don't feel like dealing with this bullshit. This car has a new top and the frame is just about perfect, and you NEVER see that up here in RI on such an old car. Interior needs work, but that's simple stuff. I don't feel like pulling out the dashboard and replacing the entire harness with another one from 85 that's probably in almost-as-bad condition.

[Vigo]

youd only need to use a fuel pressure regulator that could go down to carb fuel pressure and bypass enough volume to keep it there. If you had that you wouldnt have to change your pump setup at all.

[A.J.]

After watching the video, I'd say figure out why #1 isn't firing.

You said you tried another LM. Is that a stock one or socketed with the 3 bar cal? I had an issue with the ASD clicking like crazy and running bad with some stalling. It was a bad computer. I was dealing with a SMEC though, the LM portion of it. Also my Dad's '85 T&C wagon was stalling occasionally. We put in a Mopar hall effect and that fixed it.

As far as the smoking I'd say it's the turbo.

A.J.

[88_pacifica]

I know that you probably are frustrated as hell at this car(I've been there myself no f**king doubt)

I'm going to disagree with AJ though as it being the turbo. While the turbo MAY be leaking a little bit, if the turbo was totally bad, as soon as it boosts is when you would get the smoke cloud usually, not so much at idle. Here's a couple quick things I would do first before tearing into everything or trying to carb the thing because carbing it might not fix the core problem.

Remove O2 sensor and check in bung for oil upstream. Run a few q-tips on a straightened metal clothes-hanger and see if you are leaking upstream at the exh wheel of the turbo. If it is not soaked down in oil, I doubt your turbo is THAT bad.

After figuring that out, I would definitely run the typical compression check. That symptom with the #1 cylinder not stalling out the car while running is curious. That sure has the characteristics of a dead cylinder. I am certain you did the following right:

No heavy oil in cylinder or on plug
Changed that #1 plug to known good plug(ceramic/porcelain, electrode, gap, etc).
Pulled VC and verify the followers are in and valves are seating fully(no dropped valve seats)

If all those come back ok, then you might have to decide what you are going to do with the motor(pop HG off for a closer look, etc). Even if you carb the thing, it is unlikely that it will eliminate the smoking UNLESS it is definitely the turbo. It is hard for me to believe based on the video and what you're describing that it is entirely electrical. I DO think that you have some electrical gremlins for sure, for sure... However, you should confirm a good motor, then go on an electrical adventure.

This is I assume a pre-SMEC car so I am not very confident in my troubleshooting for those cars at all. One thing I would think about though is have a second shot at testing multiple LM's and so forth in the car. If you have somebody local that could test yours in HIS car to see if it's ok, I would start there. People always want to put a good one in their car, rather than taking the suspect one and try it in a known GOOD car. Those things are electrical and old so they are hit or miss at best, especially if exposed to elements, mice, etc.

One last question. Did the mice chew up lots of wiring and if so where? Did you already have to do "damage control" on the wires before? Maybe you can trace the wires systematically over a period of a week? one area a day?

I know you are ASE cert, but everything goes out the window on our own cars because we get frustrated and THINK we know everything about the car, but we miss the dumbest stuff...

[Vigo]

as a minor caveat to what nate is saying about the turbo, i cleaned up a garrett a while back that looked super clean, but it turned out that the area where the oil drains from the rear bearing was completely clogged with carbon. If that happens you're basically creating a pressurized chamber that will push oil past the turbine seal.

Now, if you push oil past that seal when the turbo is cold its not going to burn, so it wont smoke until it heats up. So its possible for your turbo to be leaking oil and not smoking until the metal heats up enough to make it smoke.


Sticking a pick up into where that oil drains from the back of the turbo.

Looking in from the turbine end.

All the crap that was blocking that area off.

[88_pacifica]

^^ This is true. This is usually typical of cars that have crappy oil or people that are not letting the turbo cool down sufficiently to get the cooler oil back into the turbo after beating the snot out of it. This "coking" of the oil is really common too if the coolant is less than adequate, but I would think an HG would pop on our cars before that becomes an issue on a TD. This is much more common on a GN since there are no provisions for a coolant passage.

[Big_P]

[QUOTE=88_pacifica;806540]I know that you probably are frustrated as hell at this car(I've been there myself no f**king doubt)
[quote]
Yes!

I'm going to disagree with AJ though as it being the turbo. While the turbo MAY be leaking a little bit, if the turbo was totally bad, as soon as it boosts is when you would get the smoke cloud usually, not so much at idle. Here's a couple quick things I would do first before tearing into everything or trying to carb the thing because carbing it might not fix the core problem.

Remove O2 sensor and check in bung for oil upstream. Run a few q-tips on a straightened metal clothes-hanger and see if you are leaking upstream at the exh wheel of the turbo. If it is not soaked down in oil, I doubt your turbo is THAT bad.

After figuring that out, I would definitely run the typical compression check. That symptom with the #1 cylinder not stalling out the car while running is curious. That sure has the characteristics of a dead cylinder. I am certain you did the following right:

Compression good across the board, 140 all the way across.

If all those come back ok, then you might have to decide what you are going to do with the motor(pop HG off for a closer look, etc). Even if you carb the thing, it is unlikely that it will eliminate the smoking UNLESS it is definitely the turbo. It is hard for me to believe based on the video and what you're describing that it is entirely electrical. I DO think that you have some electrical gremlins for sure, for sure... However, you should confirm a good motor, then go on an electrical adventure.

Good idea there. I just have to get it running first!

This is I assume a pre-SMEC car so I am not very confident in my troubleshooting for those cars at all. One thing I would think about though is have a second shot at testing multiple LM's and so forth in the car. If you have somebody local that could test yours in HIS car to see if it's ok, I would start there. People always want to put a good one in their car, rather than taking the suspect one and try it in a known GOOD car. Those things are electrical and old so they are hit or miss at best, especially if exposed to elements, mice, etc.

Pre-SMEC indeed! I do have another LM to try, but to my knowledge there is nobody near me with one of these cars.

One last question. Did the mice chew up lots of wiring and if so where? Did you already have to do "damage control" on the wires before? Maybe you can trace the wires systematically over a period of a week? one area a day?

I have found and repaired a few damaged spots, I just have to keep digging I guess

[88_pacifica]

Compression good across the board, 140 all the way across.


Good idea there. I just have to get it running first!


Pre-SMEC indeed! I do have another LM to try, but to my knowledge there is nobody near me with one of these cars.


I have found and repaired a few damaged spots, I just have to keep digging I guess

Pete, It is too bad that there is not an extra TM'er close to you. I would be thinking it really is a LM because there isn't much to these cars. I think it's definitely safe to say that with that good of a compression it shouldn't be a problem with the stroke/compression cycle itself. I suppose it's "possible" that it's a turbo issue, but that just doesn't sound like the symptom. Based on the color of the smoke it doesn't look fuel related either.

Like you, this is pretty confusing. I kind of wish I was there to fool with it because this sounds pretty unique. There is minimal wiring that is actually related to the engine and combustion process(only) on a TD, so I can't see why this would be happening.

Maybe you can do something else that is relatively time consuming, but has been pretty effective for me diagnosing GM's. If you disconnect the LM/ECM at the pinouts and then use an ohmmeter at one end of the wire, then a positive 12v source at the other, see what kind of drop you have in voltage across that wire. This is a long, sucky azz process, but it can often help find issues. I would start with the basic sensors(map, coolant, hep, coil, etc). I already know this is a crappy way to go, but it does work. Often the voltages may drop as the wires "move around" especially if they have been tampered with or are corroded/broken internally. Then of course, you have those damm in-line fuse circuits on these cars. If something is rubbing a contact against metal it could be sapping the voltage as well.

One other thought is make sure the ignition system is strong/functioning too. What did the plugs look like again? Gap is good(electrode not touching) and the color of plugs is right? It's not a coil obviously, but how are the wires? When you pulled that one plug wire and there was no change, that was really odd and sure acted like a dead cylinder. You made sure that the wire was seated in the cap all the way and is making positive contact on rotor, right? If it is occasionally jumping(arcing) then it would be very intermittent and could look like a host of other issues. I am almost sure you have a known good hep right(not loose)?

I am at a loss and I really wish I was there to help. Being unemployed right now I have all the time in the world to look at these things and I know that I am really just over analyzing the problems and being an armchair quarterback, which is easy to do on here.

[Big_P]

The HEP is new along with the coil. The plugs were new too. I used my best used set of cap/rotor/wires. They don't have many miles on them. Like I said I had 12v+ when cranking at both sides of the coil. Both sides .

I wish I could get you on a bus over to RI and I'd take a day outta work and we could pick through it (with mass amount of beer, of course).

I may be on to something. Aside from fixing everything under the hood, I opened the glovebox for the first time and found mice shyt. So there might be damage under the dash too. I'm going to give it two last stabs. One will be trying the other LM I have, the other will be doing what I can in terms of searching for broken wires without tearing the dashboard out.

I also remembered that in the brief time the car was running and driving, the speedometer was WAY off. At ~20mph it said I was going about 50. Relevant? I think so because it worked fine before it sat.

I also forgot to mention that the mice put acorns in the intercooler and I didn't think to check before I hooked everything up. Never thought about checking that... So as soon as I went into boost the throttle got stuck so I pulled over and found a few acorns holding the throttle plate open. Maybe one got into the engine and chewed it up. But compression is fine.

There were 5-6 other cars sitting where mine was, why couldn't they have picked a more comfy vehicle like the 04 Econoline it was right next to?

[88_pacifica]

The HEP is new along with the coil. The plugs were new too. I used my best used set of cap/rotor/wires. They don't have many miles on them. Like I said I had 12v+ when cranking at both sides of the coil. Both sides .

Wow, um.... ok... next....

I wish I could get you on a bus over to RI and I'd take a day outta work and we could pick through it (with mass amount of beer, of course).

Me too! We could BS about it as we trace some wires and look at LM's, while bltching about TD's which is typical for me.

I may be on to something. Aside from fixing everything under the hood, I opened the glovebox for the first time and found mice shyt. So there might be damage under the dash too. I'm going to give it two last stabs. One will be trying the other LM I have, the other will be doing what I can in terms of searching for broken wires without tearing the dashboard out.

I also remembered that in the brief time the car was running and driving, the speedometer was WAY off. At ~20mph it said I was going about 50. Relevant? I think so because it worked fine before it sat.

There you go. I would bet that they chewed through a wire somewhere and it is grounding out on metal and therefore sending screwy things all over the place. I mean, it's not like Chryslers had a single ground location that grounded out everything from the headlights to the bumper. They would never do such a thing.

When one is bad, everything takes a shlt...

I also forgot to mention that the mice put acorns in the intercooler and I didn't think to check before I hooked everything up. Never thought about checking that... So as soon as I went into boost the throttle got stuck so I pulled over and found a few acorns holding the throttle plate open. Maybe one got into the engine and chewed it up. But compression is fine.

There were 5-6 other cars sitting where mine was, why couldn't they have picked a more comfy vehicle like the 04 Econoline it was right next to?

I would think that the acorns would "break down" and I doubt that has much to do with the motor, HOWEVER, if some of those made it to turbo and it's binding....