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Author Topic: 1981 1.6 Diesel doesn't always start...  (Read 2895 times)

June 10, 2016, 06:09:08 pm

jhonyquest97

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1981 1.6 Diesel doesn't always start...
« on: June 10, 2016, 06:09:08 pm »
1981 1.6 caddy.  If she sits for a while, like overnight, i'll turn the key with choke and she starts right up!  Then i would drive for a while 20-40 mins and shut it off.  Then she won't start for a while.  I can hear the motor trying to start but it just isn't. It seems if i tap on the accelerator it sounds like it gets some more fuel but still doesn't start.   When she's running everything runs Great! Never hesitates, bogs down, blimps.. nothing.  Where should i start troubleshooting this issue.  This is my first diesel so i'm not to familiar with parts and what not.  Thanks.



Reply #1June 10, 2016, 06:19:16 pm

ORCoaster

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Re: 1981 1.6 Diesel doesn't always start...
« Reply #1 on: June 10, 2016, 06:19:16 pm »
I this is your first rodeo with a temperamental diesel you are likely to have some issues.  Not just with the dang car either.

I am going to go for fuel filter constriction on the first stab here.  Have you or has the previous owner replaced the filter?

It sounds like you get fuel enough to start and run for a while but then over time I think you build up a deficit in the IP and there is a vacuum on the system.  Letting it sit takes that away and you get enough fuel back to the injectors to fire it up and run it some more. 

The test here is to run it on a small quantity of fuel in a second tank, or container under the hood.  Pull the fuel from it and also return it there by pulling the line off the inlet and outlet and sticking them in the container.  If you no longer have the problem look to the fuel filter and fuel tank areas and perhaps the air inlet on the fuel tank. 

If you have to buy some additional hose to get from the IP to the temporary container get  clear line as we will potentially be using that later to find air in the system.  You can see it as it flows between the fuel.


Reply #2June 10, 2016, 06:34:49 pm

jhonyquest97

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Re: 1981 1.6 Diesel doesn't always start...
« Reply #2 on: June 10, 2016, 06:34:49 pm »
Ok... lol  i'm gonna have to get a Bentley on this one.  I've gotten my CIS-e mk2 running like a champ (3 years to do it lol), so i'll do my best to tackle this.  I know the previous owner was meticulous with upkeep.  I have the whole journal of miles and what was replaced. 

So about the build up of pressure over time.  I've driven her well over an hour with no signs of any performance change.  I do have some fuel leaking out the breather tube area near the filler tube when its full and taking left turns. However 3/4 tank and it seem fine.  I'm getting the feeling a complete strip down and testing of the fuel system in my future...

Reply #3June 10, 2016, 06:37:29 pm

jhonyquest97

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Re: 1981 1.6 Diesel doesn't always start...
« Reply #3 on: June 10, 2016, 06:37:29 pm »
So for now just let the truck run for a while, then try to start it from a secondary container?  Or just run it from the container for a bit and then start is again from that container?

Reply #4June 11, 2016, 01:07:30 am

ORCoaster

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Re: 1981 1.6 Diesel doesn't always start...
« Reply #4 on: June 11, 2016, 01:07:30 am »
Yeah, set up a secondary tank, get it running so you know it is pumping fuel around through the system and then run it a bit.  If you use a gallon tank you should be good for at least 30 miles.  So go out 10 or 12 and bring it back to the drive and shut it off.  Does it start right up again?  or would it have taken more miles than that to get the no start thing to happen?
 

Reply #5June 11, 2016, 10:49:21 am

jhonyquest97

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Re: 1981 1.6 Diesel doesn't always start...
« Reply #5 on: June 11, 2016, 10:49:21 am »
cool  i'll try this out in a few days.  I just moved so i don't have a ton of time but i'll see what i can do and post some updates.  thank you btw

Reply #6July 10, 2016, 11:43:59 am

jhonyquest97

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Re: 1981 1.6 Diesel doesn't always start...
« Reply #6 on: July 10, 2016, 11:43:59 am »
i've haven't gotten to discounting the IP into another tank yet but i did find out that the choke/cold start cable doesn't move unless i go under the hood and physically move it.  could this be an issue that might cause the starting problem?

i also hear what sounds like a pump (?) when turning the key and as is slows to almost a stop then the truck starts or almost starts...

however i expect to do the fore mentioned procedure this week!