Ford 8N sputter

[JeremysGarage]

Ok, this might be a little long winded.
I"ve got an 8N here a customer picked up. It seemed to run well when we picked it up but I really couldn"t test it much due to a bad trans. I"ve got that fixed along with many other parts bushings bearing seals guages blah blah blah. The engine, we were told that it had been over hauled by an engine shop. I"m sure that is true. it is very stong, no smoke and sound perfect. Except the sputter at idle to just below half throtle. runs good at full throtle with no load but after you start and stop a few times in 2,3,4 gear it stumbles and and spits and sputters untill you bring R"s down or bob the choke. that doesnt always work either. Ive tried adusting carb while it does this. It will clear out and then do it again after stop and go few times.
Poits are not new but are in good condition and clean set just a bit more than .015 maybee .017. timing set dead nuts continuity though points breaks at exactly 1/4 past top edge of left side mount hole.
Carb. well? I had to clean the previos ownes silicon messout of it and remove the rest of the original gasket. it has had a kit put in it. The jet, needles and throtle shaft is new as is needle and seat but the guy didn"t clean all the old gasket off and siliconed the new one in. WTF. From seeing that I wonder if he could have put the wrong kit in it. Don"t know if ther are different kits for the same carb body on these old MS"S
The other thing I"m not sure of is. This engine is quiet, almost to quiet. No valve click or so quiet I can"t here it over the exaust. Thinking not enough valve lash. Might need to pull the cover and check it out.
OH yeah this is an 8n28371 makes it a 47.
I"ve been working on late model stuff to long and I know I"m over looking something fairly simple.
Sometimes when you don"t know were to start, go back to da begining.
Just writing this helped the thought prosses a little bit
Please! if you have any good info for me, please post for me

 

[GB in MT.]

[b:44f4c23888][i:44f4c23888]
J...G...;
I do a LOT of M/S TSX overhauls here for the guys of the forum, so, maybe this will help ya!!
If the prev. owner used, form-a-gasket sil, on the half way gasket area....you can bet the passages still have some of that in them. OR, It could be that the wrong jets were installed.!!!
THAT said.....try this set-up sheet first, and if this does not help ya....then we can go from there.
If the '47' does not have a proff meter on it.....you will have to do this by ear, to try to get it done. May even have to do it 2-4 times to get it right.
The air to fuel mix needle (Idle/air adj.) sometimes is very touchy,.....so don't move it fast....just a 16th, or 32nd of a turn at a time.
Follow this sheet and hope it works for ya.:

Might be a valve-lash prob., BUT iI don't think so, as to what you posted it is doing!!!!!!

Gary [/i:44f4c23888][/b:44f4c23888]

 

[souNdguy]

.01 is getting WIDE on a front mount. i'd like to see them .014 to .016 max.. you can start getting tangible issues at .02+/-

the same carb gasket fits most ms carbs in that size.. the same kit hits the 241 and 33 variants.. .. if he used silicone.. doesn't sound like he used a kit.. as all the basic kits even, include a new gasket.

lack of valve noise on a flatty like that is not a big deal. with non adjustable, i'd guess them to be wide if anything.. not too tight.

do a comp check.. all holes blow and suck?

any hanging? occasionally you can get a sticky valve that will put thru the exhaust.. or make a miss. pretty easy to clean up.

some of the stuff you describe, assuming spark is good, could be a fuel issue.. double check good flow to and thru carb drain.. reset flaot and make sure main circuit is clean as well as idle air circuit.

post back

 

[JeremysGarage]

I was kinda leaning twards sticking valve or lash to tight, and or lack of fuel. But lack of fuel don't explain miss at idle. I know its geting enough for idle. Could be a combination of both. I've had the manifold off exaust ports where clean. No blueing or scoreing, nice and shiney and no carbon build up. The carb has had a kit put in it. All the replacables are new and shiney gasket was also new. Hense the WTF to the silicon. I'm sure I got it all out but i'll do it again just to be sure.
Any idea as to fuel flow rate at the line on the carb I should have.
I've done many carbs of all shapes and sizes. I'd have to kick my self if wasn't doing this one right! Ha ha, you never now! With the stuff I work on, when I get to work on something as simple as this I have a tendancy to over think things.
I'm gonna start from da beginin, and use the info I got from you guys. That should find and take care of the problems. Every other thing I've done on this thing, i've had to undo some one elses fancy enginering. If you know what I mean!
I know I can do all of this from the manual but its more fun talkin to you guys about it.
I post what I find

 

[DollarBill]

Any idea as to fuel flow rate at the line on the carb I should have.

Remove the drain plug from the bottom of the float bowl, with the gas turned on, you should see a continuous stream. Let it run for 30-40 seconds. Any dribbles or reduction in flow indicates a blockage. Could be any one of the three screens in the fuel system. There's one inside the fuel tank, one in the sediment bulb and one in the carb inlet fitting.

 

[JeremysGarage]

Sorry I didn't get back to you all on this thing. I've been extemly busy here. after going thru and fine tuning the dist. and carb.
She runs much better. It still putters like a sum B at an idle.

So it will be back this winter to be finished.
ther is some other issues that need to be fixed.
Next to the idle issue. this thing is the stongest 8n I have ever used.

I know the motor hase been redone. How big can you go with these things, and would it cause a jeting problem with stock jets?

 

[DollarBill]

How big can you go with these things, and would it cause a jeting problem with stock jets?

This is what I have written down:
Idle Jet Minimum Size = 0.032, Max = 0.046
Economizer Jet Minimum Size = 0.046, Max = Whatever - It's just a vent
Power Jet Minimum size = 0.043, Max = 0.053