New 1996 CCLB 3500 454. Help set my expectations on power or is there a problem

[brycebba]

Oh ok. I'm going to take it off tomorrow. If I don't see any visible leaks could I spray a little soapy water over joints and look for bubbles?

- Bryce -

 

[brycebba]

It was pouring still throughout the weekend so I couldnt pull the plenum off. I will try to do it this week but am leaving for a trip next week and might not get to it before.

 

[brycebba]

Well crap... I didn't pull off the plenum tonight because I thought I should double check the torque on the bolts. Some were pretty loose. I would guess 10 ft lbs or so but none of them were even close to 15 to 20 which I understand is the spec. So I'm cranking them back down and the 2nd one from the front on the driver side started getting easier at about 20 lbs and then it twisted and broke. Seems like one other might be a little weak. Could a loose plenum or not torqued well cause hard start issues?

It would make sense that it was great and has been getting harder and harder to start since the change.

I wouldn't do it for long but is it going to be bad to drive it on 7 bolts for a couple days?

When I do get the plenum off what tool will be best to extract the broken bolt out of the block? I have never done it before?

- Bryce -

 

[brycebba]

I had a hard start issue again when I tested it this morning so Im sure the intake bolts being loose was not good but obviously not the problem. Im not sure if I will get around to taking the plenum off for troubleshooting before I go on vacation for 10 days but I will update when I have done it. I looked at the depth of the bolt that sheered and it looks like there might be a little bit sticking out when I remove the manifold or if it stretched a lot before breaking it could be below the surface. From what I have read, if its above the surface just use vice grips and below people have many methods like easy-outs, drilling bigger and bigger holes in the bolt and picking out the threads, etc. Im going to take my time with it and make sure I dont screw up the threads or manifold surface when I do it.

 

[83GMCK2500]

If it's broke flush or below, invest in a set of left hand drill bits and start small. Sometimes just drilling them will bring them up enough to grab. Penetrating oil (not WD-friggen-40, it irritates the crap outta me when people think wd-40 is a penetrant), and try an extractor if the drilling doesn't bring it up.

GM P/N for the upper to lower manifold bolt is 12558618, if you want to replace with GM bolt.

 

[brycebba]

Sweet! Thanks man. I will order some unless it's OK or has advantages to just replace with a standard bolt with the same specs from the hardware store. I ordered a new fuel rail just in case I get back in there and it has a leak problem, I will have the part on hand

- Bryce -

 

[brycebba]

I think I found a tiny leak at the line that connects halfway up the rail so I'm lucky I ordered a new rail just in case. Big problem though and this might be a really stupid question but I pulled the rail and #4 was missing this little cap on the tip of the injectors and I can't see it down by the valve so I can only imagine it fell off and got blown out. Which injector is right?

You must be registered for see images

You must be registered for see images

I'm at a stand still. Am I screwed?

- Bryce -

 

[brycebba]

Turns out those caps are called pintle caps and they are there to help atomization of the fuel. I went to napa and got some pintle caps and replaced the other 7 so now they are all the same (napa #218015). Between the new fuel rail and pintle caps I have a very smooth idle and before my fuel pressure gauge sprung a leak I had over 50x psi. Im going to patch it tonight to get a good measurement. Strange thing is Im still having hard start issues even with no leaks. any thoughts on what else? No air leaks on fuel rail/injectors/fpr/lines to the rail. I also checked the fittings by the fuel filter just to be safe and I didnt see any leaks using the soapy water method looking for bubbles or movement. Starts awesome cold but it just cranks for a while to start when the engine is warm but has been sitting for a bit.

 

[brycebba]

Hopefully someone will help me. Update: the company sent me the old style injectors so they sent me the new style composite body injectors that don't have pintle caps and I put those in today. Pressure checks out great at about 56 psi but I still have bad hard start issues when the motor is hot and has sat for a bit. I installed a new coolant temperature sensor. When I was checking for leaks after putting in the injectors I had to turn the key on and off about 5 times for it to fully pressurize. It would basically only pressurize 10 psi at a time.

I was giving it throttle at about 2000 rpm and it died while I was going about 20. I haven't been able to get it to happen again but it feels like at certain parts of the rpm range it starves or is running too rich. What can I do next?

- Bryce -

 

[brycebba]

Oh and turning the key on and off several times to prime the pump while hot makes no difference in starting behavior

- Bryce -