JDNs78FJ40
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Idiots Guide to Holley Sniper Install (2 Viewers)
- Thread starter BenjaminCA
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BenjaminCA
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- Thread starter
- #82
It’s been a while, got back on my feet with editing and taking care of some old footage. New episode is posted and it’s the conclusion of the sniper install, with startup! Had to chase down some wiring issues, but it’s a runner.
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At last Project Wrong Way has returned !
Long Live the " Wrong Way Nation " .....
At last Project Wrong Way has returned !
Long Live the " Wrong Way Nation " .....
StinkyPig
SILVER Star
I ran into the EXACT same wiring and solenoid issue. Had some issues early on with it quitting. Updated the base tune and started over. Runs like a raped ape now.
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Welcome back..Been ”Jones’en”…
Looking for help from the Sniper gurus... I'm an idiot, looking for guidance. So far @BenjaminCA 's idiots guide has not dropped to my level of idiocy.
I've been trying to get my 40 running for a few weeks now. It seems to crank fine, and it sputters now and then but won't fire and run. I can't get Mosely Motors (where I bought it) on the phone or email for help so hoping someone here has some input.
The kit Mosely sold me is plumbed like this:
He gave me that diagram to follow, which I did.
I have the pink wire on the sniper harness tapped into ignition under the dash by fuse box.
I have the 1979 coil and igniter with fj60 distributor. Double checked all of that wiring with Haynes diagrams and replaced the fusible link with a new one from @Coolerman.
Yellow wire from sniper harness to negative on the coil as per instructions.
When cranking it the voltage drops to 10 ish and rpms are around 300. From what I understand the voltage needs to stay up at 12 and RMPS should be higher? Fuel pump is kicking on with ignition and builds pressure. When trying to start i can see fuel mist in the sniper.
A local guy that has worked on snipers was baffled an Ignition Coil Driver Module wasn't included in the kit to regulate the voltage. I had called to ask him to fine tune it for me, but he's so busy he's not interested in working on old rigs. Any ideas? Is there a better spot to tap into ignition? Not sure what to try next.
I've been trying to get my 40 running for a few weeks now. It seems to crank fine, and it sputters now and then but won't fire and run. I can't get Mosely Motors (where I bought it) on the phone or email for help so hoping someone here has some input.
The kit Mosely sold me is plumbed like this:
He gave me that diagram to follow, which I did.
I have the pink wire on the sniper harness tapped into ignition under the dash by fuse box.
I have the 1979 coil and igniter with fj60 distributor. Double checked all of that wiring with Haynes diagrams and replaced the fusible link with a new one from @Coolerman.
Yellow wire from sniper harness to negative on the coil as per instructions.
When cranking it the voltage drops to 10 ish and rpms are around 300. From what I understand the voltage needs to stay up at 12 and RMPS should be higher? Fuel pump is kicking on with ignition and builds pressure. When trying to start i can see fuel mist in the sniper.
A local guy that has worked on snipers was baffled an Ignition Coil Driver Module wasn't included in the kit to regulate the voltage. I had called to ask him to fine tune it for me, but he's so busy he's not interested in working on old rigs. Any ideas? Is there a better spot to tap into ignition? Not sure what to try next.
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Any switched 12v source is fine. 10 while cranking is fine as long as you are over 12v to start
I don’t know what your guy is talking about. Holley does not call for any ignition coil driver. I’ve done 20+ on F motors. Never had one.
Run then sputter out sounds like fuel.
Make sure your feed for fuel is on the SIDE post on the Corvette regulator. Return is center
You can also Try to eliminate it totally and run the return all the way
An in line pressure regulator may be your friend
I don’t know what your guy is talking about. Holley does not call for any ignition coil driver. I’ve done 20+ on F motors. Never had one.
Run then sputter out sounds like fuel.
Make sure your feed for fuel is on the SIDE post on the Corvette regulator. Return is center
You can also Try to eliminate it totally and run the return all the way
An in line pressure regulator may be your friend
StinkyPig
SILVER Star
Welcome to the rest of us idiots brotherhood!
There are a lot of things to check. For starters….I had to put the geared starter on the engine in order to get RPMs on starting. You may need to do this too. Amazon. Someone here will have a link.
I would also suggest that you check the voltage where you tapped into the fuse box…when cranking.
I had a horrible time with my old 78 wire harness. The fusable link in my rig was a different pink wire buried in the main harness and it was melted.
Also, check the coil.
There are a lot of things to check. For starters….I had to put the geared starter on the engine in order to get RPMs on starting. You may need to do this too. Amazon. Someone here will have a link.
I would also suggest that you check the voltage where you tapped into the fuse box…when cranking.
I had a horrible time with my old 78 wire harness. The fusable link in my rig was a different pink wire buried in the main harness and it was melted.
Also, check the coil.
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StinkyPig
SILVER Star
I also installed an inline fuel pressure gauge…one glance and you have warm fuzzy confirmation while troubleshooting.
- Joined
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Also, Holley Tech support is really good. If you give them the proper dope they can really help a lot more than most of us.
StinkyPig
SILVER Star
Thanks I actually replaced my starter with one of these.
Coil pack? Good thing (for you) that your mechanic decided not to help
Ha ha, sounds like he has more experience with the 4 barrel sniper kits. Maybe they’re different?
If you enable the data logging to the SD card, it may help shed some light on things - if you can, try a few starts with logging on and dump the file from the card here.
If it fires occasionally right on crank but never runs, that might be it running on the prime-shot. When you cycle the key, it'll give a pre-shot of fuel as prime, and it will sputter on that but not run. That's also an easy/simple check that it's at least getting fuel - have someone cycle the key and watch for the spritz.
The data log would tell for sure - but does your RPM signal appear to be happy/reliable on crank? If it's getting a good solid feed of fuel pressure, that's where'd I'd probably look next, provided the rest of the base config (# of cylinders, displacement, target AFR, etc) are also good.
If it fires occasionally right on crank but never runs, that might be it running on the prime-shot. When you cycle the key, it'll give a pre-shot of fuel as prime, and it will sputter on that but not run. That's also an easy/simple check that it's at least getting fuel - have someone cycle the key and watch for the spritz.
The data log would tell for sure - but does your RPM signal appear to be happy/reliable on crank? If it's getting a good solid feed of fuel pressure, that's where'd I'd probably look next, provided the rest of the base config (# of cylinders, displacement, target AFR, etc) are also good.
What is your battery voltage when testing at the terminals? I don't believe it will start with that low of voltage. I have never seen below 12V on my Sniper screen when cranking. For troubleshooting hook the pink wire directly to your battery and try to start the truck. Also, invest in a fuel pressure gauge and install it right before the Sniper. Without a gauge you have no idea if you have enough fuel pressure getting to the Sniper.
I'm not sure where the RPMS should be on crank but it's pretty consistent if that is what you mean by Happy. Bounces around right at 300ish.
I'll test the battery voltage tonight and try a direct wire like you suggested.
Thanks for all the suggestions everyone. I will be picking up a fuel pressure guage and will test late tonight.
I just went and did a check for giggles, as my 40 has an anti-theft kill switch. Mine will drop to 10.5ish volts while cranking, but RPM is more like 160 with the newer geared starter and a good battery.
If yours is 270ish, that might point to an issue with that signal from the coil or a misconfigured setting on the Sniper, as that seems pretty high (almost 2x). I wonder if you're set to 4 cylinders in the settings?
(EDIT: that's assuming you have a 2F...if it's a different engine, all bets are off then.)
If yours is 270ish, that might point to an issue with that signal from the coil or a misconfigured setting on the Sniper, as that seems pretty high (almost 2x). I wonder if you're set to 4 cylinders in the settings?
(EDIT: that's assuming you have a 2F...if it's a different engine, all bets are off then.)
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I was able to use the existing linkage with a hood latch bracket for my 350 TBI. May not work for the Sniper as it sits over further.
Yes I have a 2F although it was bored out for a larger piston when it was just rebuilt. I do have the sniper set up for 6 cylinder.
I spoke to a Holley tech support and he thought the RPM and voltage was fine and within range. He suggested playing around with the screw on the sniper body that adjusts fuel output (like a regular carb throttle adjuster) and if that didn't help, fuel pressure guage to eliminate a pressure issue. Where it is sputtering he thinks that adjustment screw is either closed off, or too far open. I think he told me closed off too much causes sputtering in the sniper, too open causes sputtering in the exhaust. Where it won't start and run, too far closed off makes more sense maybe? I should have monkeyed with that already, but this sniper is all new to me. I'll play with it tonight.
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