Viper 700 oil pump adjustment rich or lean

02ViperMody44

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Hello, I've read through a bunch of different posts, but I've been unable to find this answer clearly. When adjusting the oil pump adjustment gap on an '02 700 Viper, which way do you go to lean or richen the mixture? Does a larger gap richen or lean out the oil mixture. Any and all help appreciated. Thanks in advance,
Rick
 

Thanks for the reply,
I was under the impression that the shorter the gap was, the leaner it would be. Someone was told me that if you rebuilt a motor, and to immediately get more oil flowing during the initial startup, that you should pull up on the line, ...thus causing a larger gap, and it would be riching the mixture. Apparently not so.... As such I was applying this thinking to the adjustment, that the larger the gap it was actually making the mixture richer. And the shorter the gap, the leaner the mixture. As I'm actually trying to lean out the mixture as I'm going through what I think is excessive oil use, apprx. 1 qt per 100 or so miles.
 
When you pull the cable housing apart you are effectively pulling the cable inside of it. One end is attached to the throttle and doesn't move because it rests at the idle position. However the other end goes to the oil pump arm, and when you pull the housing apart, you activate the arm. In other words when you pull the housing apart (check gap) you are not changing the play in the cable, you are simply moving the play to the housing gap instead of the oil pump end.

When the arm is pulled it richens the oil mixture, so pulling the housing all the way apart sets the oil pump to max mixture regardless of what the gap is set to.

When the housing is back in place, the throttle activates the arm. The more gap that was adjusted in, the later in the throttle cycle the oil pump richens the mixture. With the cable slack (housing together and throttle at idle) the oil is set to the leanest mixture.
 
02ViperMody44 said:
I'm going through what I think is excessive oil use, apprx. 1 qt per 100 or so miles.
these guy's got ya coverd...

tell me how many gal's of gas did you use in the 100 miles????
 
I haven't refueled yet, but it was a recent rebuild, so I'm still feeling it out. I have been out driving it, but it seems to be using a lot more oil, than before the rebuild. Same oil pump used. By my fuel guage I would say there are apprx. 2 bars left.= apprx. 9 gallons used?
 
on my .04 2 bars is about 3.5 to 4 gallons left.

So a bigger gap is less oil on the Vipers???
 
Ok if you used around 9 gals that's like 36:1,,plenty rich for sure..

check your cable out make sure it's seated properly and the pump arm is
returning all the way to neutral position when idling.


and also do these checks on your cables free play....

Do these checks in this order;

1st- set idle to 16- 1,7000 rpm's(@ operating temp)

2nd- set throttle end play to 2mm(adjustment for that is down at the carb rack)

3rd- set oil pump cable free play here and here to 20(richer)to 22(leaner)mm

then set choke anytime to 1.5mm
 
Thanks for the tips.
Now I feel more confident about the adjustment. I just measured the gap at 18.58mm w/ my digital calipers. All this time I thought I was leaning it out, but I had just been riching it. Only fouled one plug though at that setting. Can't wait to reset it everthing and try it out tommorrow!
 


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