1HDT pump setup (1 Viewer)

[ToyotaHEAD]

Engine:
4.2L 1HDT (early model 92')
Turbo - Grunter Extreme running at 24PSI
Non-Intercooled presently
Pump rebuilt professionally
Injectors have new ND nozzels and setup by professionals
Pump has the "power rod" installed


I very recently rebuilt my 1HDT. The pump and injectors were also sent away to be professionally checked / rebuilt. might as well right???!!!

It seems to start and run fine (not the typical diesel loud clank clank clank sound at idle thou), and I left the pump set as per the shop that looked at it during the engine wear in period. Now that the pump has been turned up a bit the engine still makes little bottom end power/torque, and EGT climb rapidly to 1200F. (I do not want to run this engine over 1200F) The turbo also seems to take abnormally long to spool up. As in I have to be over 1700rpm with my foot right into it to get full boost. It was not like this pre-rebuild. Also the pump was adjusted to give extra fuel during off boost conditions to increase bottom end power. There is a dark puff of smoke observed if you gun the engine when idling. During hard acceleration I can also see a hint of dark smoke in the mirror, but not an obscene amount of smoke either. Another interesting note is that when the turbo is fully spooled there is this weird sound now. It will be impossible to type what it sounds like. But pre-rebuild it wasn't there. Its like a pulsing squeaky sound but only under high boost (18-24PSI). Gaskets and joints in the intake were all double checked and are ok.

My pump was installed onto the engine and never checked with the SST as per the FSM for the timing. A previous owner had left marks on the front cover and pump housing. These were aligned and the engine seemed to start and ran fine...?? This is what I would like to confirm the most. If my pump is advanced enough.

Im told a diesel will make poor power and have high EGT's if the pump is not advanced enough. The thing is, I have since *advanced* the pump within it's adjustment range to the point where the pump is almost touching the intake manifold. There is little to no room left to advance it. I double checked the mechanical timing marks (crank,pump&cam), and they are all bang on. Engine still is very quite at idle, not the typical diesel clank clank clank sound.

I am at a loss short of confirming the pump timing. Anyone have some other ideas I can try before ordering this SST?

A coworker suggested my cam timing was 180* off. Is that even possible????

This engine use to go like hell pre-rebuild. Now it feels like an absolute slug! There is a ton of goodies invested into the engine as well as the driveline from wholesale automatics. I'd really like to get it back to something resembling what it was like before.



FYI, the engine was rebuilt because 4 pistons cracked right above and inline with the wrist pins. I think this had several contributing factors. Mostly bad advice as in, i was told it was perfectly fine to run this engine up to 1450F. Hence why I am dead set on not breaking 1200F now. I can dig up pictures, or get video etc if need be to help diagnose.

Thanks everyone for any help in advance.



One off topic question as well. Is it easy to adjust the governor in the pump? In neutral my engine will only race to approx 3000rpm max. This may be due to the above mentioned problem. ^^^

 

[Cape York boy]

Sounds like fuelling. If it's not set up right you can be flat out making 1500rpm in 1st. Why don't you start at the start and be systematic in your approach. It will take a bit of time but not as much time as pulling out a stuffed engine or trying to diagnose a problem over and over.

Start with timing. Follow the manual and confirm timing. It's either TDC or BDC I can't remember. You will quickly sort out if anything is amiss. Also check on the top outer housing of your IP. There may be a mark that lines up with a mark on the timing gear case. If it doesn't adjust back to the mark. If the timing is all good you need to look at the IP. If not go see a diesel shop and most will let you borrow the sst escpecially if they did the rebuild. Take it back to spec. You can advance for a bit more power but not sure how far. Someone on here will know.

Once timing is confirmed and correct it's all about the IP. Did you get the bench test print out from the shop? I always ask for it. Some will give it to you some won't but it's a handy piece of info before you start guessing where things are at. Eg I told my shop to set pump 50% more fuel than standard @25lb boost. They set it to 50% @10lb boost. I adjusted before I even turned key.

Get the readout before adjusting if you can.

Have you played with pump settings before? You just need to think about what your doing and make adjustments. WRITE THEM DOWN. If not sure record every twist and turn. Try and do 1 adjustment at a time so you can undue the change and know what effect each change is doing.

In neutral, what happens when you stab the throttle? Is it sluggish to 3000rpm or rev really fast? If it struggles to start revving it needs fuel. Two likely causes: to tension on the afc or not enough fuel. I would adjust the arc first. Screw it all the way down. This will make it extremely sensitive to boost. Give the throttle a stab. If you get a very responsive engine then you need to start playing with the arc and pin profile. If not you need to add more fuel. Go an 1/8 of a turn at a time, stab throttle and test. Idle will increase so adjust that each time. Some say leave it so you can return to original. Just mark the initial position. Marker pen or a zip tie.

Once you get throttle response set your pin profile to where you want it, then adjust afc and shim as required. Sounds like it was defuelled a heap. My engine rebuild said he wants my engine to run at 20lb for 1st 10000km then back up to 25lb because of blow by. Might explain your lack of power. This was my experience and how I sorted it. Basically don't guess when there is something you can physically check. Hope that helps.

 

[mudgudgeon]

set the timing using the SST, anything short is a complete guess.
I found the difference in timing changed enormously just rotating the pump the width of the factory match marks (at the timing case/pump junction).

as for the governor, its not something you should adjust yourself IMO. You should be able to push the throttle to the floor with the car in neutral and have the engine rev to redline, the governor should stop it from revving beyond redline

have a read through the The Official 1HD-T/FT Fuel Pump Mod Tuning Thread in the diesel tech section. there's a load of good trouble shooting advice in the last 5-10 pages

I would expect to have to do some tuning on a rebuilt pump, but if it does sound a bit like the diesel shop has done a dog of job on your pump. if you can't improve it after some trouble shooting, I'd take it back to them