? about timing marks and a high rpm miss under load
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? about timing marks and a high rpm miss under load
My first question is about the timing marks on the case and the pump. It's my understanding that these marks were done by hand and that the original mark is only matched to the original pump installed on the motor. A new pumps timing mark would not necessarily coincide with the mark on the case to get correct timing. Am i correct on this?
I just installed a new or reman pump from II and had a lope on initial crank and idle. I felt the truck was idled low and raised it some which eliminated some of the lope. Just normal revving of the truck seemed fine with no issue. To the truck for a drive and everything seems fine until you get to high rpms and it starts to stumble. I set the pump to the same position that i removed my old pump. The mark on the pump is just a little above the mark on the case.
I'm thinking the lope at idle and stumble at high rpms is actually because the timing is retarded and needs to be pushed towards the head. Retarded timing would also cause the low idle to right?
Open to any thoughts or ideas. Also i installed 5x.014 injectors when i installed the pump.
I just installed a new or reman pump from II and had a lope on initial crank and idle. I felt the truck was idled low and raised it some which eliminated some of the lope. Just normal revving of the truck seemed fine with no issue. To the truck for a drive and everything seems fine until you get to high rpms and it starts to stumble. I set the pump to the same position that i removed my old pump. The mark on the pump is just a little above the mark on the case.
I'm thinking the lope at idle and stumble at high rpms is actually because the timing is retarded and needs to be pushed towards the head. Retarded timing would also cause the low idle to right?
Open to any thoughts or ideas. Also i installed 5x.014 injectors when i installed the pump.
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Yep, bring your timing up.
For some reason, when I did my head gasket replacement, I retarded the timing on my pump. When I put it back, I could only get to 2 of the nuts. About 2 months later, getting off the highway I had your same symptoms. I popped the hood and the IP was sitting there vibrating like it should. I advanced the throttle and it all went away.
For some reason, when I did my head gasket replacement, I retarded the timing on my pump. When I put it back, I could only get to 2 of the nuts. About 2 months later, getting off the highway I had your same symptoms. I popped the hood and the IP was sitting there vibrating like it should. I advanced the throttle and it all went away.
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Not sure what all II did to the pump our if it's the injectors but it sure is smokey when you snap the throttle up. Adjusted the timing and the idle seems much better. I'll take it out later and see how it's running under load.
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Well i bumped the timing 1/8" from the mark on the case. Got rid of the high RPM stumble but still think it's a little retarded. Great low end power but feels lacking on top end. Motor also sounds a little more noisy and off than it used to.
Does anybody know how far the top of the AFC is from the head on factory or stock setup? I'm only 1/4" from being to the head now.
Must say I'm kinda disappointed in the setup. Really not sure if i was just used to how much fuel i had from my old pump. I really want to wait out the warranty but don't know if that will really happen. I'm only making about 32lbs boost as compared to the 42 i used to make and even with the big injectors is not as smokey when running thru the gears at WOT.
Would the boost issue be a timing issue or the fact the fuel screw just isn't in that much?
Does anybody know how far the top of the AFC is from the head on factory or stock setup? I'm only 1/4" from being to the head now.
Must say I'm kinda disappointed in the setup. Really not sure if i was just used to how much fuel i had from my old pump. I really want to wait out the warranty but don't know if that will really happen. I'm only making about 32lbs boost as compared to the 42 i used to make and even with the big injectors is not as smokey when running thru the gears at WOT.
Would the boost issue be a timing issue or the fact the fuel screw just isn't in that much?
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I do think i located the problem. Apparently i somehow missed the key slot in the gear cutting half the Woodruff key off the shaft. Kind of embarrassed by the whole deal but oh well. Luckily I've got two other trashed pumps that i stole a key from. Got the truck running tonight but needs a hair of advance to work with those injectors.
Jim, pump was already set and locked by II. Luckily they mark the mounting flange where the key should line up to put the pump back at tdc in the event someone does something bone headed like i did.
Jon, I pulled the motor to tdc and locked the pump prior to removal. My way of installing it worked. The shaft was lined up with their timing mark but was obviously out of time because it was only half the key in the gear.
Jim, pump was already set and locked by II. Luckily they mark the mounting flange where the key should line up to put the pump back at tdc in the event someone does something bone headed like i did.
Jon, I pulled the motor to tdc and locked the pump prior to removal. My way of installing it worked. The shaft was lined up with their timing mark but was obviously out of time because it was only half the key in the gear.
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