13mm pump timming?

C

cumins01

New member
Joined
Nov 4, 2008
Messages
1,176
Does anyone know the thread for the spill port timming method? I looked and can't find it. I have a 13mm pump and was wanting to time it to 36* to start out with also putting on adjustable pump gear. I also have a gear drivin aux pump running off the front cover. If you remove the DV holder and internal parts can you rotate the pump to see when the port closes? Thanks for any info. If someone has a good way of doing this can you PM me so I can print it off.
Thanks,
Steve
 
Spill port timing is pretty easy. You have the right idea.

- Rotate the pump until the #1 plunger rises enough so that it covers the port in the barrel
- Turn the engine to the desired position when you want the injection period to start


* make sure to always come up on the setting going the direction of normal rotation to account for gear backlash
* usually you flow fuel through the pump to tell when the plunger closes the port



There is a small part about it in a diesel power mag article, but there are few errors in the article so I wouldn't try to live by it.
I'll look to see if there is anything in my bosch manual about it but I wouldn't count on it.
 
Last edited:
From the Article said:
By uncoupling the pump drive plate from the pump drive gear, the pump will remain stationary at port closure on the #1 cylinder while you turn the crankshaft.
Click to expand...

That is assuming the pump doesn't jump back or forward when the gear pops off. I've had several pumps that when removing the gear, it'll jump back to around 3mm. Even the slightest bump would do it on some of them. Once port closure is found, I'd put a dial in the bore so you can see if it moves, and can bring it back if it does.
 
Thanks guys. Can you see the port closure when rotating the pump? Since I have a mechanical pump (gear drivin) lift pump I can't push fuel thru the pump until the port closes. Someone told me my snap on timming tooling won't work for a 13mm pump. Is this correct?
 
No, that's wrong information. It will work just fine.

I'm not sure how accurately you'll be able to see port closure. It should get you close though. It might be worth going an autoparts store and getting the cheapest fuel pump they have to check with.

Once you know the port closure, like Tate said, you can use a dial indicator to know where that is.
 
So I can sill time it with the snap on tool like my 12mm? Or do I just use it when I know port closure is and set it in case it moves.
 
To do spill port timming you must have a seperate elec pump to feed the injection pump with high pressure wile you rotate the engine over.
 
How much pressure is needed to "force" thru the pump to check port closure?
 
You must log in or register to reply here.
Back
Top