Power loss pointing at timing slipped.

[Jeff H]

Well I had a mechanic check my truck out. My injectors were very healthy.

He said my timing is around 11. 5 to 12 degree's. At 90,000 I had it bumped up 2 degrees over spec. Spec calls out for 12. 5. So that means that my timing was at 14. 5.

My mileage went down. My performance is doggy. I asked him if he would adjust it to 14 to 15 degrees. He set he would only set it at spec. I told him not to adjust. Because his way of doing timing was wierd. Kind of like adjusting like a 6. 2 chev diesel. So I'm gonna find someone else to do my timing. I really wish I could do timing.

 

[Reddog1]

I too would like to adjust my timing. I have the ’96 Shop Manual, but it is still not real clear to me.



It appears you must have some kind of shim kit. If my understanding is correct, you shim by guess and by golly, check indicator reading then guess and by golly again, repeating until you get it right.



I have not set the timing nor have I seen the process done. I am definitely interested.





Wayne

 

[JohnE]

Jeff;



It would a bit of a drive for you, but I found a local (to me) diesel peformance shop.



<strike>MIKES'S</strike> MIKE'S CUSTOM TRUCK BUILDERS in Northwood, ND.

Mike Adams is a real nice guy and drives a 12v 3500 with considerable performance upgrades. We talked on timing. He has gone as high as 20&deg;.

Give him a call at 701-587-6335



-John

<font size=1>I am not an employee of nor a compensated representative of Mike's Custom Truck Builders.

I corrected a mispell</font>

 

[JJW_ND]

If you talk nice to any of the Cummins North Central shops and agree (sign) that you will not hold them lible for damage caused by overspec timing, they might set it for you.



Then again Northwood is not to far from anywhere in MN to have it done. I spoke with Mike a while back. He has a Dynojet and will do a before and after timing set if you want. If you loose power it will show up.



Plan on heading that direction myself soon.



jjw

ND

 

[shendren]

talk to cummins employee Jim Jessup. he is the most knowledgable person on the b series engine. period... . he told me that 99/100 he looks at has the timing fubar'd by whoever touches it. he'll tell you what is going on. if you live in indiana, it would be worth the time to make an appointment with him. you stay with the truck and he walks you thru everything. i mean everything. you feel much better when you leave. and have a perfectly tuned up b series. good luck. scott.

 

[Joe G.]

Wayne,



You have to have a special tool kit to do the timing. Also a torque wrench that will indicate at least 165 ft/lb. The kit contains some shims as part of the tool. Basically what you do is loosen the pump drive gear and turn it until the timing is correct. Then tighten it up again. There is more to it than that of course but that's the idea. The tool kit contains a dial indicator that is used to check and set the delivery valve lift at TDC for correct timeing. You also need a chart of what the stock timing is for your pump. If you don't have a Dodge service manual for your truck you REALLY REALLY should have one!! I'm about 350 miles from you so not much help.

 

[JohnE]

thanks jjw

I forgot to mention the dynojet in Mike's west stall. Did he get his ATS Pulse exhaust manifold installed yet?



FWIW

Cummins standard training is to set timing by flow. They look for a delivery valve to give a set number of drips in a 30 second window.



-John

 

[Reddog1]

I have the shop manual, torque wrench and dial indicator. TSB 18-11-96 has injection pump timing specs. The chart for 49 state autos goes from 13 to 15 degrees, depending on plunger lift (?). This appears to be . 16 mm of lift per each degree.



Does the rotating of the pump drive gear change the plunger lift? Are there degree marks on the pump drive gear?



Any idea what would be the typical time required to adjust the timing? Cost?





Wayne



P. S. I am currently an Educator. I was a machinist in one of my previous lives (pre-Educator).

 

[Joe G.]

The timing gear is on a tapered shaft. The nut holds it on very tightly so it won't slip. The amount of lift at TDC indicates the timing. You need a puller to break the gear loose from the shaft. No timing marks on anything. The first thing to do is locate TDC as accurately as possible. Then measure the lift in the first delivery valve at TDC so you know what your timing is. Read the description of the procedure in your manual carefully.

 

[Reddog1]

Thanks Joe.



I forgot about the gear puller. I do have one.



It would appear the torque (on the nut) is particularly critical, to prevent the gear from slipping. It also suggests to have oil on the taper (during assembly) could result in improper torque value.



It also appears that re-positioning the timing gear is by guess and by golly, with an indicator check after the torque process.



Any idea what would be typical of the time required to adjust the timing?





Wayne

 

[Joe G.]

If you don't have the tool kit you need it. There is a barring tool in the kit so it's easy to turn the engine BOTH ways. There is also a pin that is used for the dial indicator to measure delivery valve lift after you remove some parts. It fits down inside the valve barrel. The dial indicator in the kit attaches to the delivery valve. After you find TDC then if the timing is not correct rotate the engine until the dial indicator indicates the desired lift. Pull the gear. Rotate the engine to TDC. You need to do this in the normal direction because of gear lash so you have to back it up past TDC and then rotate to TDC. Clean the tapered shaft with brake cleaner. The gear is too big to come out the opening so you just spray thru the hole. Torque up the gear nut. Torqueing up the nut changed the timing a little bit on mine so I had to repeat the process until I got it right. The first time you do this it will take two or three hours. Read the manual carefully before doing this.



EDIT: Any oil on the tapered shaft causes the thing to slip!! So it MUST be clean or you walk. The barring tool also revents the engine from turning when you torque up the nut.

 

[Reddog1]

Joe, you have done a great job in explaining the timing process. Of the numerous posts I have read, yours are the best. Thanks for your time and the sharing of your knowledge.



By the BY, any idea what the cost of the Took Kit is? Can you buy the barring Tool separately? My machinist tools include no less than 14 different types of dial indicators, and I would not want to guess at the number of pins.



Wayne

 

[Joe G.]

I got my tool kit from: http://www.spxmiller.com/ I have no idea what the price is now. As far as I can remember it was something like $180. When I considered the price of a couple of hours at the Peterbilt shop and having the tool kit myself I went ahead and bought it.



I dunno if Miller has the barring tool separately or not. I think you can get it from Dodge for something like $50 but I'm not sure. Snapon may carry it. Anybody would be less than Dodge. You might want to give Swift Dodge on Arden Way a call and see what they have to say. I've bought a few parts from them and they seem to know what they are doing in the parts department. They may have it in stock. The Dodge dealer in Eureka checks with them first if what I want is not in stock here.

 

[Jeff H]

Sounds good. But truly would have too see a demonstration though. Even a video would be nice too see.

I think I check out that place John E was telling me about.

 

[HoleshotHolset]

I'll shoot the video if someone wants to do the demonstration... . I'll even volunteer my truck!



Matt (television production engineer)

 

[JohnE]

Jeff;



Mike is usually open on Saturday, too.

Let me know if you decide to come up for some work. I'l drive over and we can make a party of the affair. I want to look at Mike's rig and try help him on the EGT problem.



I should have my ESPAR install done one of these days. You can take a look at it.



-John