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-   -   Sputters except when WOT (https://www.nopistons.com/1st-generation-specific-16/sputters-except-when-wot-70847/)

BigBadWolf 10-06-2008 09:12 PM

After cruising along at 95-100 for a while, I was pulled over(I know, surprise surprise!). Officer friendly had me cut off the engine, I guess he isn't a fan of throaty exhausts. When I restarted it sputtered like hell except when WOT, then I runs perfectly. Pulled in to rest area and discovered one of the vacuum caps was gone from spacer, which has me baffled. I recapped but still had same symptom. Figured I still had a vacuum leak somewhere, and took my chances with rest of drive from Orlando to Ft. Lauderdale since I was half-way there. Didn't smoke or overheat, and gas consumption remained normal. When I got to my Dad's house I let it cool down since it would die if I let it idle. Did the old WD-40 check at every cap and hose(I removed the rats nest a couple of years ago), ran a little better when choked, but found no leak. Sprayed around intake, air pump block off, all sides of Nikki carb, back to canister, zero degree tank, etc. still found nothing. Put in new lead plugs, checked the igniters(DLIDFIS), and the dizzy to see if the advance got stuck. Thought maybe the secondary diaphragm was stuck out since I'd removed the spring, but replacing spring when I got back home and that didn't help either. Yes, 240 miles of stuttering back with temp and mileage normal. WTF!!! Before I rebuild the carb is there something I'm missing? Was running perfectly until I was busted. This is an '83 12A w/stock Nikki carb.

PLEASE, any advise would be greatly appreciated by me and my neighbors(I go to work @ 6-6:30am).

TheRX7Project 10-07-2008 05:31 AM

It must not be running rich, or else you'd have more fuel consumption. Maybe your car didn't like being ran at 90-100 for a prolonged period of time?

BigBadWolf 10-07-2008 07:50 PM


Originally Posted by TheRX7Project' post='909382' date='Oct 7 2008, 06:31 AM
It must not be running rich, or else you'd have more fuel consumption. Maybe your car didn't like being ran at 90-100 for a prolonged period of time?

Was perfectly happy when I shut it off. Your right it's definitely not too rich, no smoke and runs best while choke is on. I've run it at 120-130 for 30 to 60 minutes recently without any issue, and that's before I switched trani's to an '87 which dropped rpms by over 500. I'm picking up a carb rebuild kit tomorrow, and pray that solves it. Sounds just like a timing problem till I give it some gas.

j9fd3s 10-08-2008 12:43 PM

i would have a look at the acv blockoff plate, i had one where the air pump came apart, and the peices got stuck in those passeages, and its a vacuum leak, and a real bastard to find too cause spraying around the outside of the engine wont find it.

BigBadWolf 10-08-2008 05:42 PM


Originally Posted by j9fd3s' post='909494' date='Oct 8 2008, 01:43 PM
i would have a look at the acv blockoff plate, i had one where the air pump came apart, and the peices got stuck in those passeages, and its a vacuum leak, and a real bastard to find too cause spraying around the outside of the engine wont find it.

I did the rats nest a couple years ago. There's something behind the plate that could be causing this problem?

j9fd3s 10-08-2008 06:01 PM


Originally Posted by BigBadWolf' post='909517' date='Oct 8 2008, 03:42 PM
I did the rats nest a couple years ago. There's something behind the plate that could be causing this problem?



if the plates leaking, yes.

BigBadWolf 10-08-2008 06:15 PM


Originally Posted by j9fd3s' post='909518' date='Oct 8 2008, 07:01 PM
if the plates leaking, yes.

Gotcha, your saying the plate could be leaking and all the WD-40 in the world won't show it.

BigBadWolf 10-08-2008 10:01 PM

WooHoo!

I can't tell you how much I appreciate your taking the time to offer some suggestions. After replacing every vacuum hose on the left side, and resealing the plate, I was ready to call it a night when it was staring me right in the face. It was the part I will forever refer to as the f'ing 1/2" stub pipe just below the elbow tube on the intake. Where the original cap and cap on the spacer ever went I'll never know. I suspect they melted into oblivion while waiting for my 96mph ticket. I can't believe I was able to drive 350 miles at 70-80 and several days to work and back with a hole that big on my intake. True testament to the reliability of our rotary engines!

Again, thank you so much for responding. You kept me damned and determined to find the problem without rebuilding the carb.

By the way, love the avatar. It's perfect for the state we're in, and the choices we've been given by the 2 major parties. I can't take it, I'm voting for Barr. Let the dumbmasses do what they want.

TheRX7Project 10-09-2008 07:56 AM

So you're going to waste your vote?

j9fd3s 10-09-2008 10:36 AM


Originally Posted by BigBadWolf' post='909558' date='Oct 8 2008, 08:01 PM
WooHoo!

I can't tell you how much I appreciate your taking the time to offer some suggestions. After replacing every vacuum hose on the left side, and resealing the plate, I was ready to call it a night when it was staring me right in the face. It was the part I will forever refer to as the f'ing 1/2" stub pipe just below the elbow tube on the intake. Where the original cap and cap on the spacer ever went I'll never know. I suspect they melted into oblivion while waiting for my 96mph ticket. I can't believe I was able to drive 350 miles at 70-80 and several days to work and back with a hole that big on my intake. True testament to the reliability of our rotary engines!

Again, thank you so much for responding. You kept me damned and determined to find the problem without rebuilding the carb.

By the way, love the avatar. It's perfect for the state we're in, and the choices we've been given by the 2 major parties. I can't take it, I'm voting for Barr. Let the dumbmasses do what they want.



sweet! ive rebuilt a bunch of carbs, and its never fixed anything


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