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B21ft no-start

adamdrives

Member
Joined
Aug 9, 2010
Location
San Jose
Car: 83 245 turbo

Issue: car won?t start because the cylinders are filling with fuel. .

History: I bought the car non-running, limped it into the shop, got it to idle and drive but not well. Discovered a cache of forlorn k-jet parts and went to town preparing engine for swappage into my 242. After replacing wire harness, WUR, and cleaning fuel distributor (FD), car wont start and injectors are going full blast whenever the pump is running.

What I?ve checked: shaft is not binding/stuck in FD, no debris or torn o-rings in FD, metering flap is not stuck and moves freely, all electrical and fuel line connections are in correct positions.

My theory: based on what I?ve learned about the system, the injectors are getting full fuel pressure (or more than none/a little which is what I believe they should be getting with the flap in resting position, ie no airflow) because something is allowing fuel to pass through the FD unmetered.

Question: does anything other than the FD shaft, controlled by the metering flap, control volume of fuel passing through the FD?
 
The control plunger should be able to control the flow of fuel to the injectors. If it's not stuck is it possible it was installed upside down?
 
I installed it with the tapered side down, o-ring side up.

Also, my k-jet book says there should be a spring above the plunger on 83 and later models. Either I lost the spring (don?t remember one coming out) or it?s missing.
 
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The goal is to keep this as cheep as possible, but if I can't figure out the issue I may throw in the towel (wallet) even though an MS'd b230ft is starting sound more and more reasonable.
 
As always the first question with K-jet is "what are the fuel pressure readings?"

In addition to the FD the Control Pressure Regulator or also known as the Warm Up Regulator plays a significant role in injector operation.

I know you say that the FD control plunger is not stuck but that would seem the most likely issue. Remove the top connection of the FD and apply air pressure to ensure that it is not.

Here is a link to everything you wanted to know about the K-jet system: http://forums.turbobricks.com/showthread.php?t=289775

I know that the FD appears to be a simple device but I have opened two, one lived, one did not.
 
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Yeah, I'm thinking I killed it. Not sure why, but didn't have this issue before I ****ed with it.

I also replaced the WUR while I was doing the fuel lines, I am going to double check part numbers to make sure it's the correct one. Reading the WUR link makes me wonder if control pressure is too low and there's too little resistance to the plunger moving up. But, there's no airflow with just the pump primed so that doesn't seem the only explanation.

I think I had messaged you about an 8mm banjo, that's all I'm missing to set up my fuel pressure testing rig.
 
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Adam, I sent that connector well before Christmas. I have another one if it never got there.

In my trials with the Bertone at one point I was successful in getting the injectors to spray enough fuel into the cylinders to hydro lock the engine. Guess that should be petro lock.

Getting a FD back together would not appear to be a insurmountable task but many have tried and failed. Mostly leaks.

Try the air pressure at the top center and see if it is a stuck control plunger. Quick shot of 40psi air should dislodge it if that is the problem.

A stuck control plunger is about the only thing that would cause a continuous flow of fuel to the injectors at enough pressure to open them.

There must be 30+ WUR part numbers specific to meet emission requirements. Being in CA a correct one might be important.
 
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No luck with applying air pressure to the top of the plunger. As it is, cylinders 2 and 3 flow like crazy, but 1 and 4 just a fine mist. I have the injectors out of the head and spraying into cups. Probably about a 1/4 of a regular white paper coffee cup in 10 seconds or so.
 
Sounds like the little 'O' rings on the side of the control plunger are cut or out of place. Since you have had it apart already you can't hurt it any more. Did you use a rebuild kit?
 
Injectors should atomize fuel not spray it. So you do have two injectors with a bad spray pattern. The two that flow like crazy are supposed to be spraying the fine mist you see in the two good ones. They usually respond well to cleaning but finding a shop with the injector test rig is rare now.
 
I also am with the folks suggesting you double check the plunger. I'd remove the FD and see how the plunger moves. It should drop right down if you push it up inside. In other words it should move freely to the point where it can drop out if you aren't careful. Anything more than that means it's binding.

Also check the rest position bracket for the air flow plate. If the adjustment got bent or moved it could have the air flow plate too high in the rest position. Same goes for the air/fuel mixture screw.
 
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1. The o-rings are all in good shape. I didn't use a rebuild kit, just some viton o-rings that matched the size.

2. The plunger does bind when pushed in all the way. When I install the FD, I let the plunger move down to the metering arm, then let the FD down over it. So, presumably the plunger is in resting idle position. I tried blowing air in to move the plunger down just in case, but the injectors still buzz with only the pump primed. The CIS Greenbook says that if the injectors buzz with the plate down the plunger has jammed. Presumably that's to describe what would happen after the metering flap has moved the plunger upwards and it sticks. In my case I can be pretty sure its not binding in an upwards position.

3. I remembered that the first time I took the FD apart all the shims (washers?) fell out from underneath the springs that sit in each of the four chambers. I'm not sure if those are shims that need to be a particular width, or washers. Probably shims. Even so, why would a tiny difference make the injectors go full blast? There were two washers behind each spring, they all appear to be the same width, and they don't have a precise machined look like valve shims.

4. I know that I need to try a new FD. I just want to understand what went wrong, and not waste more time/money.
 
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Injectors should atomize fuel not spray it. So you do have two injectors with a bad spray pattern. The two that flow like crazy are supposed to be spraying the fine mist you see in the two good ones. They usually respond well to cleaning but finding a shop with the injector test rig is rare now.

What kills me is that we had an injector tester in the shop when I arrived a few months ago. I had personally never touched (or seen) a k-jet car at this point, and had no idea what I was looking at. When the owner retired and had to clear his decade worth of **** out of the shop (he had an RV, speedboat, a dozen crates filled with clay machines) we were tossing **** into the dump truck for the scrap yard. It was crunch time and we were getting rid of anything not needed. I probably held it in my hand, didn't recognize it as valuable, and tossed it in... :grrr:
 
Can anyone take pictures, or have access to, complete fuel and vacuum hose diagrams? I want to be 100% sure I have everything right.
 
There is a separate barb on the intake manifold for the TVS (thermal vacuum switch). It's a little hard to see because it's under the cold start valve.

TurboK-JetColdEnrichment.jpg


Turbos don't use the small vacuum connection on the flame trap.

B21FT_PCV.jpg
 
Okay, that's the barb post throttle body, so I have that right. Good to know re flame trap nipple, I'll just block it off.
 
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