Injector pump problem

[Rattler]

My son had the injector pump replaced on his 93 because it was leaking fuel pretty bad. He called today and said it started and ran ok, but when you tried to accelerate, it popped and didn't run well. The new pump came from Midwest Diesel Injection. Could this be an install problem or a pump problem?

 

[jclark5810]

Sounds like the pump timing is off, who did the install?

 

[Rattler]

Kinda what I was thinking Joe. A mechanic freind that my son used to work for did the install. He is a good mechanic, just not real experienced on diesels. How can you check timing short of pulling it all back out?

 

[NIsaacs]

If he got the gears in time and he probably did, it still needs timed with a special tool if he did not use/have one. It is a special dial indicator that measures plunger lift in mm's, I bought mine from Cummins.

Nick

 

[DVolk]

You can install and get in time with out a dia indicator

 

[JFN]

You can install and get in time with out a dia indicator

Care to share your method?

 

[Rattler]

I to would like to know how to time it. I have a magnetic base indicator, its just that I am not home yet. I could possibly check the timing this weekend if you explain the method.

 

[cerberusiam]

It is more than likely a pump problem if it started and idled ok. Unless the pump gears was purposely jogged around when the old pump removed and new one installed you have 2 choices for install, correct and 180 out. One way will run, the other won't even start.

If the trucks starts good, idles good, doesn't smoke white like crazy look for the pump to be the problem. Even then, it may not be a pump problem but the wrong pump build. The timing curves on a these engines were different in a multitude of vehicles. You could take one from a bread truck install it in a pickup and it will start, run, and accelerate. What happens is the timing curve is way off and under hard acceleration it will start popping, nose over, and throw tons of white smoke. Under easy acceleration it will seem to run fine.

You can get them close with a dial indicator but to do it exactly takes a gauge on the back of the pump to measure lift at degrees of rotation. For the most part, it is not needed if the stock timing and pump is used.

 

[mweiman]

Just a thought but what about low lift pump pressure and is the fuel filter good? Just a thought since you said it idled ok.
Matt

 

[DVolk]

Whom ever put the pump on did they pull the cover off or leave the cover on ?

Was the timing pin used so nothing would move ? if you follow the proceedure in the book it will run .

My guess you got a bad pump , im out a $1000. 00 for a pump i bought from a socalled reputal pump shop found on e-bay in Tennesse , it ran good for maybe a month it had internal problems and rust issues from a bad build .

I will only use very popular reputal shops and preferbilly local shops from now on .

 

[Rattler]

I should get to see the truck myself this weekend. I have been gone for work is the reason my son had somebody else do the install.

 

[mysteryman]

It is unlikely that it was installed incorrectly. Yes the timing could be wrong. But it can't be all that wrong and still run. There are 3 studs on the gear case that the pump mounts to. The pump has slots to allow it to be rotated on the studs. If the stud is in the middle of the slot you are very close to having correct timing. . As a rule, If the timing is too far retarded the truck will blow a lot of white smoke and be sluggish on takeoff . Too much advance causes excessive cylinder pressure which causes a lot of loud knocking noises and blown head gaskets/piston ring lands ect.



Your problem is most likely low fuel pressure. Check your fuel pressure at your lift pump. Be sure that there are no vacuum leaks in the fuel line from the tank to the lift pump. Be sure that there are not any rust pin holes in the sending unit . If all this checks out. Take the pump back to where it came from.

My son had the injector pump replaced on his 93 because it was leaking fuel pretty bad. He called today and said it started and ran ok, but when you tried to accelerate, it popped and didn't run well. The new pump came from Midwest Diesel Injection. Could this be an install problem or a pump problem?

 

[Rattler]

WE finally had a chance to look at the pump last night. The pump was all the way to one end of the slot. It started fine, but it was down on power. We moved the pump until it was in the middle of the slots, my son said the truck ran much better.

 

[DVolk]

Most of the pumps come from the builder " Locked in Time " thats the reason for the bolt on the pump

 

[mysteryman]

Standing on the drivers of the truck and looking at the injection pump. Advancing the timing would be when you rotate the top of the pump towards the engine. We like advance ! (to a point) retard really sucks. Try pushing it 1/8 th of an inch past the center in the advance direction... . I also intend to make a video of replacing and timing the pumps as well. I will post it on youtube... Good luck ... ///MM

WE finally had a chance to look at the pump last night. The pump was all the way to one end of the slot. It started fine, but it was down on power. We moved the pump until it was in the middle of the slots, my son said the truck ran much better.

 

[Rhett144]

The greatest problems are the pressure of the fuel(safety) support with 0 pressure, and the timing must be kept proper for ease of start up and set up.
It is very heavy.

 

[mysteryman]

This is true, But if you really want the timing to be correct you really need to check it with a dial indicator and readjust accordingly after initial installation . The locked rotor method is to just get you in the ball part for the initial installation... . Everyone that owns one of these trucks should own this dial indicator's.

Most of the pumps come from the builder " Locked in Time " thats the reason for the bolt on the pump

 

[Rattler]

I am well versed in using a dial indicator, but I don't know what to check on these first gens. It would have helped if I had done the install.

 

[Greenleaf]

I will bet hard earned money that when you turned the pump, you turned it to push the top of said pump closer to the engine cyl head... ... ... ... ...

Ask me how I know... ... ... .



At this stage, if it woke the truck up, then all you need to do is adjust the timing so it don't ping like the 5-cyl engines. I like mine to jump up into the tree when I snap the throttle. Any more than that, it will ping and cause higher HP issues (under load).

 

[Rattler]

Your right. I did rotate the top of the pump towards the head.