Max Speed 35 mph

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muttguru
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Re: Max Speed 35 mph

Unread post by muttguru » July 12th, 2020, 6:49 pm

See post below:-
Last edited by muttguru on July 12th, 2020, 6:54 pm, edited 1 time in total.
Kind regards....
Ken

Always wanted - Details and pictures of M416 Trailer data plates & M151 data plates & body-tags for my research. Thanks!

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Note for 2023..... Ken..."Less Stress - More Exercise!"

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muttguru
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Re: Max Speed 35 mph

Unread post by muttguru » July 12th, 2020, 6:52 pm

muttguru wrote:
July 12th, 2020, 6:49 pm
It looks like you have the leads positioned correctly.

Image

I noticed that you have an in-line fuel filter. Why not remove that filter for a while and connect the fuel pump directly to the carb? (most of you know my views on in-line filters). And what about that fuel cap....is it vented or not?
And...erm....what are those clothes-pegs doing?

Ken
Kind regards....
Ken

Always wanted - Details and pictures of M416 Trailer data plates & M151 data plates & body-tags for my research. Thanks!

Contact address - - muttguru@aol.com

Note for 2023..... Ken..."Less Stress - More Exercise!"

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rickf
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Re: Max Speed 35 mph

Unread post by rickf » July 12th, 2020, 7:26 pm

Ken and his hate of fuel filters! I would do a fuel flow check instead of removing the filter. Take the fuel line off at the carb and crank the engine with the line in a can and see what kind of flow you have. You should have strong spurts of gas and a pretty good amount of flow. If it is just barely dribbling out then remove the filter and try it without the filter and see if you get better results. If you do then the filter is clogged which means it did it's job. If you still get just dribbling then either the pump is bad or there is a restriction before the pump. You will need to put a vacuum gauge in the line between the pump and the incoming line. If you get a vacuum reading then you have a restriction. Another thing to check is for air in the line coming in. Replace the section after the inline filter with a piece of clear line from the hardware store and see if there is air in the fuel coming in. If there is then you have a leak in one of the lines from the tank to the pump.
1964 M151A1
1984 M1008
1967 M416
04/1952 M100
12/1952 M100- Departed
AN/TSQ-114A Trailblazer- Gone

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Re: Max Speed 35 mph

Unread post by Husker » July 12th, 2020, 7:59 pm

Thanks!
Yea every post I search though with a fuel problem has ken against the filters!! It’s brand new and has only been used since I put the power pack back in with new fuel lines.

I am getting good flow at lower speeds. Went for a drive and I really have a similar issue to where I was at before this whole thing started.... able to go up the hill out of my neighborhood and make the first turn to the next hill if I’m going to fast it bucks. Was able to make it around the block and go downhill over 40. But coming around the other side I had to stop twice to what it felt like refill the bowl so either my float setting is still bad or I do have poor fuel flow

I’m going to try to isolate parts of the system tomorrow I’ll be using rubber tubing into a gas cab with fresh gas and see how it goes that will see if any of my bends in the fuel lines are really that bad
US Army Fort Belvoir

19XX M35 something. Sold......
1972 M151A2
1967 M416
On the hunt for an M1031

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Re: Max Speed 35 mph

Unread post by rickf » July 12th, 2020, 9:06 pm

That sounds exactly like what Ken is saying about the gas cap vent being closed! Try loosening the gas cap and see if the problem goes away. If the vent is closed then as you use gas and no air can get in to replace it there is a vacuum created which eventually overcomes the pump. This usually takes quite a while if you have a decent pump. it is not something that happens in the first minute. I have seen it take as much as 20 miles or or more but when the cap was opened there was a hell of a whoosh!
If you have not physically verified by looking at the flow coming out of the line then you can't say you have good flow just based on the fact that it goes up the hill once. You need to physically see things to verify what is happening or you will be chasing this problem forever. Are you still running the old stale gas? I would go so far as to say you need to check the fuel pressure also. The pump may not be delivering the right pressure. It also may not be delivering the right volume, this is why I say you have to actually see it. Those diaphragms get stiff from age and alcohol and they can fail without actually leaking.
1964 M151A1
1984 M1008
1967 M416
04/1952 M100
12/1952 M100- Departed
AN/TSQ-114A Trailblazer- Gone

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Re: Max Speed 35 mph

Unread post by Husker » July 12th, 2020, 9:50 pm

I did attempt the drive with the gas cap open to no change

I’m currently using the new slant 6 pump
I have a military pump on the shelf I can try as well
I will check fuel pressure if I can get someone over to crank it
US Army Fort Belvoir

19XX M35 something. Sold......
1972 M151A2
1967 M416
On the hunt for an M1031

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Re: Max Speed 35 mph

Unread post by Husker » July 18th, 2020, 5:01 pm

Well I got new plugs they seem a lot better but now I can’t get it to idle anymore and ran out of timing on the backside of the distributor (pushed it all the way back and still barley in time

I think it’s due to my tac dwell set messing up idk what’s wrong with it but it’s now reading I think at least a lot lower then it was before that or i was just bogging the finless brown trout out of the engine before and my ear for its idle rpm isn’t good

I have a vacuum gauge I can try to check for leaks or similar? Only other change from before is the coil it’s a different one I thought my old one could be dying I didn’t know so I swapped another I had on the shelf
US Army Fort Belvoir

19XX M35 something. Sold......
1972 M151A2
1967 M416
On the hunt for an M1031

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Re: Max Speed 35 mph

Unread post by Husker » July 18th, 2020, 8:01 pm

Points distributor worked great straight out after gap was set passed dwell fine and engine idled better the The Swiss controls one I thought


I had been checking fuel pressure at the hose not that secondary fuel filter and it was clogged a win for ken if there ever was one
My primary filter is new I replace it often but had not swapped the seconday one at the carb in over a year
US Army Fort Belvoir

19XX M35 something. Sold......
1972 M151A2
1967 M416
On the hunt for an M1031

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Re: Max Speed 35 mph

Unread post by rickf » July 19th, 2020, 10:22 am

Now back up here a minute, You are saying the filter AT the carb was clogged? If so then that would not point to a bad inline filter and therefor would not be a win for ken. It WOULD be a win for me because it pointed out exactly what I said to check. But if that filter was clogged then it had to have been clogged since before you put in the inline filter. The inline filter will stop anything that would come even close to clogging the stock filter, unless you are using the bargain basement e-bay inline filters. I only use brand name filters mostly WIX whenever possible. My filter on the carb has actually been drilled out so it is only there for looks. And even though I have the usual residue in my tank I get nothing in the carb. And no restriction from the inline filter. Sorry Ken. This is one we will never agree on. :lol:

And on your ignition, was it a REAL Swiss controls module or one of the Chinese knock offs that are on the market now? Finding a real one now is like finding a NOS coil.
And I saw a video on you tube of you setting you idle and to me that idle sounded a lot lower than the 800 showing on the meter. That looks like an old military tune up set, are you sure it is calibrated?
1964 M151A1
1984 M1008
1967 M416
04/1952 M100
12/1952 M100- Departed
AN/TSQ-114A Trailblazer- Gone

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Re: Max Speed 35 mph

Unread post by Husker » July 19th, 2020, 11:24 am

Napa part number is 3046 for the carb fuel filter

It is an old military set no It has no manual calibration for the RPM only for the dwell side of the meter.... it has been what I was using the whole time for trying to get this to run right maybe I have just been setting my idle to low the whole time?

I have a vacuum gauge as well but am unfamiliar with how to set idle using that
US Army Fort Belvoir

19XX M35 something. Sold......
1972 M151A2
1967 M416
On the hunt for an M1031

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Re: Max Speed 35 mph

Unread post by rickf » July 19th, 2020, 11:34 am

Thats the one that was clogged? There is nothing wrong with only using the one filter, the main reason for the second inline filter is so you can see the gas flow and if you gave a dirty filter considering all of the running issues these vehicles have. Sometimes it is a lot easier when you look and see there is no gas coming through the line and now you know you have a fuel issue and you can skip the rest of the stuff. Or vice versa, you see gas moving through then you move on to ignition.

And like I said, if that is the one that was clogged it was that way before you put the inline filter on so it has been causing you trouble for a while. And get yourself a much newer cheap tach/dwell unit, I would not trust a 50 year old military surplus unit that was surplused out for unknown reasons. When using points always set the points first and the timing last since points setting change will change timing.Setting points with a dwell meter is nice but setting them with a feeler gauge works just as well. It was done that way for 50 years before dwell meters became the hot new thing in tune up tools.
As for setting the idle turn it down until the hood stops vibrating. Sounds weird? You will see what I mean after you try it a few times. You do not want the idle so low that the generator does not charge at idle. If it is an A2 you won't have this issue with the alternator. What you want is for it to be idling low enough that the centrifugal advance in the distributor is not advancing the timing. It is hard to tell on a video but the idle you had sounded good to me. It also sounded much lower than the 850 reading.
1964 M151A1
1984 M1008
1967 M416
04/1952 M100
12/1952 M100- Departed
AN/TSQ-114A Trailblazer- Gone

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Re: Max Speed 35 mph

Unread post by Husker » July 19th, 2020, 12:01 pm

Thanks rick

Even with the quick replacement of the filter the settings I had seemed solid enough
Was able to drive all around my neighborhood and get up to 50MPH to drive to Wendy’s for some lemonade lol

I’ll shop around for a more modern tac

I set the points with a feeler gauge first then just hooked up the dwell cause I had it

Jeep runs better then it ever did before at least and best of all my rebuilt transmission works!
US Army Fort Belvoir

19XX M35 something. Sold......
1972 M151A2
1967 M416
On the hunt for an M1031

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Re: Max Speed 35 mph

Unread post by m3a1 » July 19th, 2020, 5:18 pm

So very glad to hear your MUTT is behaving now!

All of this drives home a very simple point. It's the little things that get ya.

As always -

BASICS
BASICS
BASICS

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