Dying Under Load

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65_Stang_170
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Dying Under Load

Post #1 by 65_Stang_170 » Sat May 12, 2018 5:34 pm

Howdy!

Just got everything hooked up after swapping to an 1101 and distributor from a '69 250. I think I have the timing and A/F ratio in a pretty good spot. It idles really well, but when I rev up beyond 1500 rpm it stumbles quite a bit. When I tried to drive it out of the garage, I couldn't fully release the clutch without it dying. So, now it's in the driveway while I troubleshoot... Thoughts? Maybe a vacuum leak or something?
1965 Mustang Coupe - 170 I6, 3.03 Manual Transmission, Autolite 1101 Carb
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falcon_master
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Re: Dying Under Load

Post #2 by falcon_master » Sat May 12, 2018 7:08 pm

I am in no way even close to an expert but I would think that it's a carburetor problem if it stumbles after a certain rpm it could be on of the fuel circuits not working right or the timing not advancing properly. Someone correct me if I'm wrong please
High School AFJROTC cadet and car enthusiast. Likes all things ford and engines of any company. 64 falcon 2dr sedan with 144 six and "3 on the tree" column shift manual transmission. Still in make it move stage.

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chad
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Re: Dying Under Load

Post #3 by chad » Sat May 12, 2018 8:27 pm

falcon_master wrote:...could be on of the fuel circuits not working right or the timing not advancing properly. Someone correct me if I'm wrong please

no, I think ur right but w/o bein there I'd say double ck timing 1st, then onto carb if needed (also very far frm ex - spirt)...
"Big thing is only make one change at a time. Change 2 or more things at a time it becomes difficult to figure which change helped or hurt" turbo2256b » 1/16/2017
Chad - '70 LUEB on '77 frame (i.e. PS, D44, trapezoidal BB 9", 4.11), 250, NV 3550 & DSII to B transplanted, "T" D20/PTO, 2" SL, 1" BL, 4 discs, 33"X15", etc. Seeking: Hydraulic gear motor for Koenig pto. chrlsful@aol.com (413) 259-1749

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wsa111
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Re: Dying Under Load

Post #4 by wsa111 » Sat May 12, 2018 8:41 pm

At idle in neutral can you bring the rpms up to 4500 with no load?? if not hook a timing light up & see if you have a steady spark or it jumps around?? If so you may have reverse polarity.
What is your ignition system?? What is your fuel pressure??
Need more info to really pin point your problem. Bill
67 mustang,C-4, with mod. 80 hd, custom 500 cfm carb with annular boosters, hooker headers, dual exh.-X pipe, flowmaster mufflers, duraspark II dist. with MSD-6AL. Engine 205" .030" over with offset ground crank & 1.65 roller rockers. 9.5 comp., Isky 262 cam.
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65_Stang_170
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Re: Dying Under Load

Post #5 by 65_Stang_170 » Sat May 12, 2018 9:08 pm

Ignition system is a stock distributor and coil from a '69 250. Mechanical fuel pump, so whatever psi that make. I don't have a gauge to test, but its pumping well/normal. I have a manual transmission, and in neutral when I press on the accelerator to bring up the RPMs it goes smooth until about 1500. I continued to press through up to 3500 RPMs and it continued to shake/stumble pretty good. When I put it in first and tried to go it cut out pretty quickly even if I really babied it.

Thanks for the help!
1965 Mustang Coupe - 170 I6, 3.03 Manual Transmission, Autolite 1101 Carb
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wsa111
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Re: Dying Under Load

Post #6 by wsa111 » Sat May 12, 2018 10:02 pm

You have an ignition problem from what you describe.
However just try this, when you bring up the rpms, slightly close the choke blade to richen the mixture.
Disconnect the vacuum advance & see if that makes a difference??
67 mustang,C-4, with mod. 80 hd, custom 500 cfm carb with annular boosters, hooker headers, dual exh.-X pipe, flowmaster mufflers, duraspark II dist. with MSD-6AL. Engine 205" .030" over with offset ground crank & 1.65 roller rockers. 9.5 comp., Isky 262 cam.
2003 Ford Lightning daily driver. Recurving Distributors. billythedistributorman@live.com
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Re: Dying Under Load

Post #7 by Econoline » Sat May 12, 2018 11:59 pm

I'd pull the top and see if all the check balls and the weight are there and in the right place. And check the float while in there.
Respectfully,

Seth

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Re: Dying Under Load

Post #8 by 65_Stang_170 » Sun May 13, 2018 2:33 pm

wsa111 wrote:You have an ignition problem from what you describe.
However just try this, when you bring up the rpms, slightly close the choke blade to richen the mixture.
Disconnect the vacuum advance & see if that makes a difference??


Thanks Bill. I'll give it a shot and see what happens.

Econoline wrote:I'd pull the top and see if all the check balls and the weight are there and in the right place. And check the float while in there.


I just rebuilt it and the check ball and weight are in the designated spot. Based on the diagram at least.
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Re: Dying Under Load

Post #9 by 65_Stang_170 » Mon May 14, 2018 7:48 pm

wsa111 wrote:You have an ignition problem from what you describe.
However just try this, when you bring up the rpms, slightly close the choke blade to richen the mixture.
Disconnect the vacuum advance & see if that makes a difference??


Just got a chance to try what you suggested: disconnecting the vacuum advance did not seem to change anything. However, closing the choke a bit seemingly cured the issue, and it was smooth and not stumbling up to 3500 rpm. What does this mean?

Thanks!
1965 Mustang Coupe - 170 I6, 3.03 Manual Transmission, Autolite 1101 Carb
No Upgrades at this time.

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wsa111
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Re: Dying Under Load

Post #10 by wsa111 » Mon May 14, 2018 9:14 pm

You either have a jet clogged or too lean a jet. Need to remove the top of carb & make sure each & every passage is clean. Make sure float level is correct & make sure the float drops when float bowl is empty.
Hope you don't have a major vacuum leak.
Do you have the correct pcv for your engine size? Or do you have a draft tube??
What is the # on the main jet??
67 mustang,C-4, with mod. 80 hd, custom 500 cfm carb with annular boosters, hooker headers, dual exh.-X pipe, flowmaster mufflers, duraspark II dist. with MSD-6AL. Engine 205" .030" over with offset ground crank & 1.65 roller rockers. 9.5 comp., Isky 262 cam.
2003 Ford Lightning daily driver. Recurving Distributors. billythedistributorman@live.com
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65_Stang_170
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Re: Dying Under Load

Post #11 by 65_Stang_170 » Mon May 14, 2018 9:57 pm

wsa111 wrote:You either have a jet clogged or too lean a jet. Need to remove the top of carb & make sure each & every passage is clean. Make sure float level is correct & make sure the float drops when float bowl is empty.
Hope you don't have a major vacuum leak.
Do you have the correct pcv for your engine size? Or do you have a draft tube??
What is the # on the main jet??


I just pulled the carb apart to make sure everything was adjusted correctly. Float was adjusted when I rebuilt it, and drops as it should with fuel decrease. Current jet is a 61F. I believe I have the correct pcv size for my engine, as it was working just fine before I switched out carbs/distributor. I think I did fix a slight vacuum leak by tightening down the new adapter plate, so we're getting somewhere. I think I need to get a new hose for the PCV as it isn't sealing completely at the vacuum port. Tomorrow's project...
1965 Mustang Coupe - 170 I6, 3.03 Manual Transmission, Autolite 1101 Carb
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wsa111
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Re: Dying Under Load

Post #12 by wsa111 » Mon May 14, 2018 10:07 pm

Per your carb. what is the original main jet size for your carb. ???
Put in a 68 jet & see what happens.
67 mustang,C-4, with mod. 80 hd, custom 500 cfm carb with annular boosters, hooker headers, dual exh.-X pipe, flowmaster mufflers, duraspark II dist. with MSD-6AL. Engine 205" .030" over with offset ground crank & 1.65 roller rockers. 9.5 comp., Isky 262 cam.
2003 Ford Lightning daily driver. Recurving Distributors. billythedistributorman@live.com
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JackFish
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Re: Dying Under Load

Post #13 by JackFish » Mon May 14, 2018 10:11 pm

Sounds like you've gone over the carb pretty well.

Put a timing light on it and see if you're getting proper advance.
If not check the distributor springs.
1978 Ford Fairmont station wagon
1978 Ford Fairmont station wagon
Yup, I bought another one.
1996 Chevy Caprice 9C1 (3)
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65_Stang_170
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Re: Dying Under Load

Post #14 by 65_Stang_170 » Tue May 15, 2018 8:17 am

wsa111 wrote:Per your carb. what is the original main jet size for your carb. ???
Put in a 68 jet & see what happens.


A 68 Jet was in it originally, but I figured smaller engine = smaller jet? I'll get it switched out tonight and see how that affects everything. Ok, two projects for tonight. New PCV hose and switch the jet.

JackFish wrote:Sounds like you've gone over the carb pretty well.

Put a timing light on it and see if you're getting proper advance.
If not check the distributor springs.


How do you check how far it has advanced if the timing tab only goes to 14? I've always wondered this...
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Re: Dying Under Load

Post #15 by drag-200stang » Tue May 15, 2018 8:53 am

Other than the accelerator pump shot, a carburetor is not a fuel injector...It gets sucked in, a smaller engine means less suck and less fuel, to a point it is self adjusting...There is a lot more to it , best to use your air fuel meter.
66 Mustang Coupe
200 turbo w/lenco 4-spd
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best 1/4 mile ET 9.85/best mph 139 on 8 lbs progressing to 15 lbs boost
Went 9's when 10's was fast.

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Re: Dying Under Load

Post #16 by 65_Stang_170 » Tue May 15, 2018 8:32 pm

Put in the 68 jet and it seems to be running much better. Got a new hose for the PCV, but I don't know if that affected anything. I was able to drive it around the block, and it felt ok. Need to make a few more adjustments, but moving in the right direction. I give a go again tomorrow, but the battery died (separate charging issue).

On a separate note (charging issue): what are the ramifications for running the car without a voltage regulator? I can't get my charging system to work: new battery, alternator tested several times, tried a few new voltage regulators. It's not giving the battery enough juice to stay charged, so it slowly drains... I accidentally left the VR unplugged, and the alt dummy light didn't light up anymore, and the battery was getting enough juice. Thoughts?
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chad
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Voltage regulator

Post #17 by chad » Tue May 15, 2018 10:19 pm

"...Thoughts?"
only 1 as I'm no help on electrics (or much else but...)
I've heard the VR are NOT made as well as they once were (is much?) & that many have gone thru enuff w/o gettin a good 1 so as to rebuild an old 1...
C if U can get a Motorcraft? NAPA - Elchign (spelling)?
"Big thing is only make one change at a time. Change 2 or more things at a time it becomes difficult to figure which change helped or hurt" turbo2256b » 1/16/2017
Chad - '70 LUEB on '77 frame (i.e. PS, D44, trapezoidal BB 9", 4.11), 250, NV 3550 & DSII to B transplanted, "T" D20/PTO, 2" SL, 1" BL, 4 discs, 33"X15", etc. Seeking: Hydraulic gear motor for Koenig pto. chrlsful@aol.com (413) 259-1749

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JackFish
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Re: Dying Under Load

Post #18 by JackFish » Wed May 16, 2018 2:26 am

You need a timing light with an advance dial to check anything over idle.
And if all you're doing is driving around the block it won't charge the battery.
1978 Ford Fairmont station wagon
1978 Ford Fairmont station wagon
Yup, I bought another one.
1996 Chevy Caprice 9C1 (3)
1999 Dodge Ram 2500

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Re: Voltage regulator

Post #19 by 65_Stang_170 » Wed May 16, 2018 7:39 am

chad wrote:"...Thoughts?"
only 1 as I'm no help on electrics (or much else but...)
I've heard the VR are NOT made as well as they once were (is much?) & that many have gone thru enuff w/o gettin a good 1 so as to rebuild an old 1...
C if U can get a Motorcraft? NAPA - Elchign (spelling)?


I've tried a motorcraft/autolite mechanical VR and a few solid state VRs, and neither allow enough voltage to the battery while the car is running.

JackFish wrote:You need a timing light with an advance dial to check anything over idle.
And if all you're doing is driving around the block it won't charge the battery.


Copy, need a fancy timing light. I know driving around the block won't charge the battery. I've taken it out on longer trips and have had the charging system checked while it was running. The battery wasn't getting the full 14ish volts even while holding it at a higher rpm.
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Re: Dying Under Load

Post #20 by JackFish » Wed May 16, 2018 5:22 pm

How are the battery cables?
Who tested the alternator for you?
1978 Ford Fairmont station wagon
1978 Ford Fairmont station wagon
Yup, I bought another one.
1996 Chevy Caprice 9C1 (3)
1999 Dodge Ram 2500

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Re: Dying Under Load

Post #21 by 65_Stang_170 » Wed May 16, 2018 9:03 pm

JackFish wrote:How are the battery cables?
Who tested the alternator for you?


Battery cables are in good condition. I've had the alternator tested in and out of the car several times at both O'Reilly's and Autozone. And my father-in-law and I tested it at home, and it checked out. I also put in a new alternator wiring harness. I got a new plug for the VR that I need to wire in to see if that's where the fault is.
1965 Mustang Coupe - 170 I6, 3.03 Manual Transmission, Autolite 1101 Carb
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Re: Dying Under Load

Post #22 by 65_Stang_170 » Thu May 17, 2018 4:22 pm

Got her tuned pretty good for now, and she's running pretty strong! Best it's ever felt?

Thanks for the help everyone!
1965 Mustang Coupe - 170 I6, 3.03 Manual Transmission, Autolite 1101 Carb
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Re: Dying Under Load

Post #23 by Soldmy66 » Thu May 17, 2018 6:00 pm

Might want to double-check the fuel filter too.

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chad
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CONGRATS !!!

Post #24 by chad » Thu May 17, 2018 8:46 pm

so:
jet
harness
VR
(& pcv?). Is that what it wuz? OR - timing too?
"Big thing is only make one change at a time. Change 2 or more things at a time it becomes difficult to figure which change helped or hurt" turbo2256b » 1/16/2017
Chad - '70 LUEB on '77 frame (i.e. PS, D44, trapezoidal BB 9", 4.11), 250, NV 3550 & DSII to B transplanted, "T" D20/PTO, 2" SL, 1" BL, 4 discs, 33"X15", etc. Seeking: Hydraulic gear motor for Koenig pto. chrlsful@aol.com (413) 259-1749

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Re: CONGRATS !!!

Post #25 by 65_Stang_170 » Fri May 18, 2018 2:15 pm

chad wrote:so:
jet
harness
VR
(& pcv?). Is that what it wuz? OR - timing too?


Timing was solid the whole time. The jet made a big difference. New vacuum hoses also helped the situation.

Haven't figured out the charging system issue yet, but that's future me's problem... :lol:
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wsa111
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Re: Dying Under Load

Post #26 by wsa111 » Fri May 18, 2018 8:24 pm

Amazing the jet change was what i said before, now is the time to upgrade your distributor for a real performance gain. Bill
67 mustang,C-4, with mod. 80 hd, custom 500 cfm carb with annular boosters, hooker headers, dual exh.-X pipe, flowmaster mufflers, duraspark II dist. with MSD-6AL. Engine 205" .030" over with offset ground crank & 1.65 roller rockers. 9.5 comp., Isky 262 cam.
2003 Ford Lightning daily driver. Recurving Distributors. billythedistributorman@live.com
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