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  #16  
Old 01-07-2018, 05:18 PM
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Originally Posted by Diseasel300 View Post
This is a big difference from "not being able to move". 2000 RPM should be moving the car, maybe not very fast, but consider that in a factory condition, you're doing ~1500 RPM to drive 30mph...

You may have issues with the ALDA system which is preventing the turbo from spooling due to the fuel being cut way back. Do you have a line running from the intake manifold to the ALDA? If not, there's your problem. If you do, try taking it apart at the intake manifold and see if the banjo bolt is all full of carbon. Barring all else, try removing the ALDA unit from the injection pump and see where that gets you. Without fuel enrichment to spool the turbo, you'll be driving a gutless wonder.


I've actually done a custom manifold and turbo system for this exact engine about 11 years ago when my friend owned an 85 and I drive it about 15 mikes with a blown turbo and it run better than mine does now . Even with the turbo completely bypassing gases and not spooling it would still move more than it does now . The more I keep looking at it the more I think it's a fuel related problem which is load dependent . Compression is great , not only does it always start on the first try but it barely turns before it starts and once it starts I can feel the engine running strong and the throttle response is great . Just to reverse it output my garage and up my gradual driveway it struggles, I can hit the pedal all the way down and i can still walk faster uphill than it's going . I've been around turboed cars for years but my only experience with these was doing a custom turbo setup on a friends car and someone he knew at the time in Tennessee did the running for him . I do not want to start taking things apart and making what could be a simple problem worse , I may be extremely knowledgeable on turbocharged modern cars but I'm quick to admit I do not know anything about these . Any and all help is greatly appreciated so please keep the ideas coming and thanks for taking the time to answer my post .
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  #17  
Old 01-07-2018, 05:29 PM
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What is the first gear ratio of the 727 compared to what a 722.X Mercedes 4 spd trans would be? Also, you have a very heavy vehicle with large tires (I am assuming here). Even in say a W126 (heaviest MB Diesel car), the car does not accelerate very fast, but once the turbo spools up, it will scoot right along. If your Wagoneer has low range, try driving it. If you feel the turbo spool up right away, then you found your problem- too tall gear ratio, or not low enough first gear. Just my .02
EDIT: I once had a '74 Cherokee (same size as the Wagoneer, but only 2 doors) that I put a 500 cu in Cadillac engine in. Even with all that HP, it was a slug off the line. It did work pretty good off road in low range though.....Rich
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  #18  
Old 01-07-2018, 05:40 PM
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Originally Posted by Ltpro View Post
I've actually done a custom manifold and turbo system for this exact engine about 11 years ago when my friend owned an 85 and I drive it about 15 mikes with a blown turbo and it run better than mine does now . Even with the turbo completely bypassing gases and not spooling it would still move more than it does now . The more I keep looking at it the more I think it's a fuel related problem which is load dependent . Compression is great , not only does it always start on the first try but it barely turns before it starts and once it starts I can feel the engine running strong and the throttle response is great . Just to reverse it output my garage and up my gradual driveway it struggles, I can hit the pedal all the way down and i can still walk faster uphill than it's going . I've been around turboed cars for years but my only experience with these was doing a custom turbo setup on a friends car and someone he knew at the time in Tennessee did the running for him . I do not want to start taking things apart and making what could be a simple problem worse , I may be extremely knowledgeable on turbocharged modern cars but I'm quick to admit I do not know anything about these . Any and all help is greatly appreciated so please keep the ideas coming and thanks for taking the time to answer my post .
You're missing the point of my previous post. There is an ALDA module on top of the injection pump, it looks like a square thing bolted to the top. It's entire purpose is to restrict fuel until the turbo begins to build pressure, then it will increase fuelling to allow the turbo to do its job and the engine to make its rated horsepower.

You say you made a custom manifold - did you send a sensing line to the ALDA? If not, you will never build boost, you will never get fuel enrichment, and the engine will have maybe 30HP and a complete inability to do any useful work.

To test the theory, delete the ALDA. You'll need a couple wrenches to break it free. If you suddenly have power, you know where your problem lies. In neutral and without load, the engine will rev just fine because it is not being asked to do any work and the turbo is not spooled. With the fuel cut way back, it'll rev just like nothing's wrong.
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  #19  
Old 01-07-2018, 08:59 PM
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Originally Posted by Diseasel300 View Post
You're missing the point of my previous post. There is an ALDA module on top of the injection pump, it looks like a square thing bolted to the top. It's entire purpose is to restrict fuel until the turbo begins to build pressure, then it will increase fuelling to allow the turbo to do its job and the engine to make its rated horsepower.

You say you made a custom manifold - did you send a sensing line to the ALDA? If not, you will never build boost, you will never get fuel enrichment, and the engine will have maybe 30HP and a complete inability to do any useful work.

To test the theory, delete the ALDA. You'll need a couple wrenches to break it free. If you suddenly have power, you know where your problem lies. In neutral and without load, the engine will rev just fine because it is not being asked to do any work and the turbo is not spooled. With the fuel cut way back, it'll rev just like nothing's wrong.

I again thank you for your reply but you may have missed my point as well . I posted what I did in an attempt to inform you that I have good knowledge on turbos and I will always sort to what I know best first to eliminate that as a possible cause . I had already sent a boost reference to the ALDA and I just double checked it just to make sure , I even took the port off the intake and double checked that as well . I also just took it up and down the street again and it sure feels like its lacking fuel . I will delete the ALDA tomorrow morning and report my findings , I sure hope thats the problem . I also plan to take off the lift pump and visually inspect that for possible obstructions , I'll do that after I delete the ALDA - from what I've read and you've told me that may be my issue . Thanks again for the reply ..
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  #20  
Old 01-07-2018, 09:06 PM
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Quote:
Originally Posted by ROLLGUY View Post
What is the first gear ratio of the 727 compared to what a 722.X Mercedes 4 spd trans would be? Also, you have a very heavy vehicle with large tires (I am assuming here). Even in say a W126 (heaviest MB Diesel car), the car does not accelerate very fast, but once the turbo spools up, it will scoot right along. If your Wagoneer has low range, try driving it. If you feel the turbo spool up right away, then you found your problem- too tall gear ratio, or not low enough first gear. Just my .02
EDIT: I once had a '74 Cherokee (same size as the Wagoneer, but only 2 doors) that I put a 500 cu in Cadillac engine in. Even with all that HP, it was a slug off the line. It did work pretty good off road in low range though.....Rich

I wish that was the problem , this thing cannot get out its way - if my butt dyno is correct ( and its always on the money ) I have maybe 40hp at best . From what Diseasel300 posted and from everything else I've read it appears it may be some issue with the ALDA or I've been also wondering if theres an obstruction either in the lift pump or elsewhere . I'm completely out my element on this one but I've learned a lot in these pass few days .
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  #21  
Old 01-07-2018, 09:12 PM
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Originally Posted by Ltpro View Post
I again thank you for your reply but you may have missed my point as well . I posted what I did in an attempt to inform you that I have good knowledge on turbos and I will always sort to what I know best first to eliminate that as a possible cause . I had already sent a boost reference to the ALDA and I just double checked it just to make sure , I even took the port off the intake and double checked that as well . I also just took it up and down the street again and it sure feels like its lacking fuel . I will delete the ALDA tomorrow morning and report my findings , I sure hope thats the problem . I also plan to take off the lift pump and visually inspect that for possible obstructions , I'll do that after I delete the ALDA - from what I've read and you've told me that may be my issue . Thanks again for the reply ..
It's easy enough to check the fuel supply. Pipe the fuel return into a bucket or bottle. At idle you should have a solid stream of fuel returning to the bottle or bucket and it should be free of bubbles or foam. A wimpy trickle, intermittent flow, or foamy stream indicate fuel supply issues. If you rev the engine, the flow should pick up with RPM.
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The Diseasel Thread - Everything You Didn't Know You Wanted To Know
Delivery Valve as Source of Nailing Thread
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  #22  
Old 01-07-2018, 09:41 PM
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Originally Posted by Diseasel300 View Post
It's easy enough to check the fuel supply. Pipe the fuel return into a bucket or bottle. At idle you should have a solid stream of fuel returning to the bottle or bucket and it should be free of bubbles or foam. A wimpy trickle, intermittent flow, or foamy stream indicate fuel supply issues. If you rev the engine, the flow should pick up with RPM.

This post solidifies I have a fuel problem . The return hose is spiting out the fuel erratically and very little , since I'm not familiar I figured that was normal . So the ALDA or the lift pump should be my issues , yet again I appreciate your help ....
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  #23  
Old 01-07-2018, 09:55 PM
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Which primer handle do you have on your lift pump? Is it the white handle that you unscrew, or is it the later one-piece black one? If the earlier white one, it is very well known for leaking air, especially if it spills fuel when you manually pump it, and should be replaced as your first step.
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The Diseasel Thread - Everything You Didn't Know You Wanted To Know
Delivery Valve as Source of Nailing Thread
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  #24  
Old 01-07-2018, 10:40 PM
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Originally Posted by Diseasel300 View Post
Which primer handle do you have on your lift pump? Is it the white handle that you unscrew, or is it the later one-piece black one? If the earlier white one, it is very well known for leaking air, especially if it spills fuel when you manually pump it, and should be replaced as your first step.
I've got the white one and yeah when I pumped it spilled fuel , I guess that's not supposed to happen - lol . To me it wouldn't be odd if it spilled fuel a bit while you prime it , I have one on order . Thanks
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  #25  
Old 01-07-2018, 10:47 PM
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The white handle seems to be a very common source of air ingress in the fuel system. There are quite a few threads on this forum alone about it, typically replacing the leaky primer handle resolves or greatly improves things. Not an expensive part and a good place to start.
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'83 500SL Euro - "The Money Pit" 116K
'86 300SDL - "The Diseasel" 180K
The Diseasel Thread - Everything You Didn't Know You Wanted To Know
Delivery Valve as Source of Nailing Thread
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  #26  
Old 01-07-2018, 10:57 PM
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Originally Posted by Diseasel300 View Post
The white handle seems to be a very common source of air ingress in the fuel system. There are quite a few threads on this forum alone about it, typically replacing the leaky primer handle resolves or greatly improves things. Not an expensive part and a good place to start.

Yeap , thats one of the first things I ordered - comes in tomorrow . I look forward to having this running right , this engine sounds really healthy .
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  #27  
Old 01-08-2018, 07:55 AM
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Took the ALDA off this morning and that did nothing , next step is to remove the lift-pump and inspect it .
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  #28  
Old 01-10-2018, 02:13 AM
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Still waiting on a few parts to come in. It continues to start right up and run great , its making about 12lbs of boost but makes no power when the boost kicks in so I'm definitely looking at a fuel starvation issue .
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  #29  
Old 01-10-2018, 10:46 AM
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How are you measuring boost? If you're actually making 12PSI of boost under load, the engine is doing all it can and the injection pump is delivering adequate fuel to spool the turbo to maximum output. If you had a fuel starvation issue, the turbo would NOT be spooling.
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'86 300SDL - "The Diseasel" 180K
The Diseasel Thread - Everything You Didn't Know You Wanted To Know
Delivery Valve as Source of Nailing Thread
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  #30  
Old 01-10-2018, 04:01 PM
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FWIW the turbo will spool to full boost with the ALDA line venting to atmosphere (experienced that on the one road trip I did with my wagon)
(Edit: Not to imply OP's ALDA isn't, just saying it doesn't need that much fuel to spool the turbo)
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