Of TF999's Snipers and 258 Ignitions

Mancunian

Basic User
CJ-8.com Member
City
Bridgeport
State
WV
#1
It took 2 months to resolve this, my woes may help someone else.

Background, rebuilt TF999 with lockup torque convertor, partially rebuilt 258.
Holley Sniper EFI, stock coil, GM HEI module mounted to stock distributor.

The EFI
Got the engine running fine, except that i noticed that the engine was idling a bit high, could not get it to idle below about 750 rpm, there are various help guides for the sniper that talk about how to fix high idle issues, but 750 was as low as it gets for this engine. Jeep guys at work said not to worry, so on we go.

The Transmission
So we try to put it in gear, stall! From Neutral into drive or from Park into Reverse it would stall more often than not, i could move it but it wasn't drive-able.
You can use one of the inputs on the sniper to add idle speed when not in park or drive, so i added a relay and wiring and programmed the EFI to try that - not much better.:(
I probably spent a week adjusting timing, chasing vacuum leaks sealing off the EGR ported vac vs. manifold and adjusting EFI parameters
Had the rear on jack stands so i could put it in drive and then apply the brakes, still xxxxx stalling

So at some point and after talking to the guy we purchased the torque convertor from we decided we must have bu....ed up the Torqueflite valvebody rebuild somehow, so off it comes.
I was also a bit concerned with the torque convertor itself, maybe it's just locking up due to a fault.
It (TF999) was also leaking from behind the torque convertor - so it really had to come out anyway.

To cut that story short, the valves and springs all seemed correct, the pump had a ~0.004 gap at the lower side where the ports are - i believe that was the cause of the leak- spewing oil through a relief just above the valve body causing the fluid to aerate and come out of the overflow. (Moral be careful when using an impact puller on the TF999 to remove the pump, the lower thread for the puller is close to the pump pressure exit).
We took the torque convertor back to the shop and asked their opinion, he thinks it's ok, will return it for us, but says that when the manufacturer tests it he doubt's they will find an issue.

Get Transmission back on - connect everything else up - I'm getting faster at this unfortunately.

And it still stalls.:banghead::banghead: at this point i loose interest for a couple days and do some long overdue house projects.

Pretty much convinced that the torque convertor is bad, but really not looking forwards to taking it off again. After all what else could it be?

The Ignition
Still with me?
So nagging thoughts that the correct idle speed should be something like 550 rpm, not 750 rpm. So decided to upgrade the ignition before pulling the transmission again. Another $150 - oh well.
I went the Ford TFI route as has been documented elsewhere, new E coil and distributor cap and plug leads from an F150.
20191121_172610.jpg
AND What a night and day difference! Idle speed could now be reduced to 550 rpm and the beast would actually go into gear without stalling.(y)

It's not over yet, but at least i can move the thing onto the driveway without my wife and son asking if i pushed it...
 

jammer1

Scrambler Junkie
LIFETIME
CJ-8.com Member
City
Maple Hts.
State
Oh
#2
It can drive you crazy trying to fix a problem that there's no clear cut reason why it's not running right. Glad you were able to find the problem. It's good info to know.
 

Mancunian

Basic User
CJ-8.com Member
City
Bridgeport
State
WV
#4
So why would the other ignition system not work?
Not 100% sure, my guess is that there was a problem with the distributor cap or coil that i couldn't see, eg. crossfiring in some way. The 'new' cap is at least 50% bigger so should result in the spark going where it's meant to.
 
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