6.9 Pump Timing

[nightrunner84]

I rebuilt this motor some time ago, but yesterday was the first chance I had to really tow something. It was a 5000lb 5th wheel. Well, the EGT's ran at about 1000 degrees and it had a really hard time maintaining highway speeds. I set the pump loke the manual said, but with the high exhaust temps, doesn't that mean that the timing is too far retarded? Here is a picture of the marks.

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Can I safely bump the timing, and if so, which way do I turn it?

 

[Kevin 007]

Setting the pump timing to the mark is just a way of getting the pump in the ball park so it will run. One should use a diesel timing meter to set it bang on. Im also guilty of not using a meter when I should. A lot of people can get it pretty close going by the sound, smoke, starting etc...but you can still be off.
Yes, I believe high egt's are a result of retarded timing. But you were working it pretty hard. how much smoke?

If you want to experiment you could advance it a bit and see how it reacts via starting, smoke, egts, sound etc. But this is the redneck way of doing it, not the proper way. I do it the redneck way

 

[nightrunner84]

it was smoking, not heavy, but just enough that I could see it with the left side mirror. which way do i turn the pump for advance? How far should it turn it? My problem is that this is a pretty useless truck if it can't pull a small load like that. There's gotta be a way to get more power out of it, or there is something wrong?

 

[Kevin 007]

You rotate the pump towards the passenger side of the truck to advance it. Only move it about a dimes width at a time. You will notice a difference if you pump is in fact reatrded, or it may get worse if its already too advanced. Try it. Just don't run the engine without at least two of the nuts that secure the pump, torqued down well.

 

[nightrunner84]

Nice, that's exactly what i was looking for. one thing that I forgot to mention. Even when the EGT's were high, the coolant temp never went up.
Do I advance till the coolant temp starts to come up under load, then back it off a little?

 

[chevytaHOE5674]

You should track down a timing meter and time it that way.

 

[Kevin 007]

X2, and if you advance your timing to the point where your coolant temp rises more then usual, you have gone way too far lol. Do you have a aftermarket temp gauge? Cause the factory ones are useless.

 

[swampbear]

I'd love to know more about this aswell, As far as I know the pump has never been timed, Nor the valves been adjusted, I couldn't find any specs on the process of either, If You've been down that road, could you PM me? I don't want to highjack this post nor start a repeat one lol, Thanks

 

[Kevin 007]

Valves don't need adjusting in these rigs, they have hydraulic lifters.

 

[Wyreth]

One trick to timing it by ear, is to hot the cold advance solenoid. Then bump it a dimes width at a time. You will hear it start to rattle "like a powerstroke" and it really does. When it just starts to rattle, stop, and unplug the cold advance. It should quiet down to that IDI growl. If it doesn't stop rattling when you unplug it, you've gone too far, and should back off a bit.

Keep in mind this is very subjective, and not accurate, but can help.

If you want to get it right, and trust me you do. You can buy a meter, or a ferret adapter, or rent one from Gary (icanfixall)

 

[Agnem]

I rebuilt this motor some time ago, but yesterday was the first chance I had to really tow something. It was a 5000lb 5th wheel. Well, the EGT's ran at about 1000 degrees and it had a really hard time maintaining highway speeds. I set the pump loke the manual said, but with the high exhaust temps, doesn't that mean that the timing is too far retarded? Here is a picture of the marks.

You must be registered for see images attach

Can I safely bump the timing, and if so, which way do I turn it?

You should attend the IDI Weekend coming up at the end of the month. We will be doing timing clinics in Toledo.

 

[hesutton]

The truck is NA correct? What gears are in the axles? My experience with NA IDI's has shown me that even modest loads (light than the one you were pulling) will shoot the EGT's through the roof. A turbo will help keep the EGT's more reasonable and add power to move the load. Gear is another issue. If you've got 3.55's, you'd notice an improvment in the pulling abilities of your rig with 4.10's.

Yes, proper timing will help keep the EGT's in check, but they will be elevated (regardless of the timing) with an NA IDI that is being worked.

Heath