| View previous topic :: View next topic |
| Author |
Message |
horse
Member
Joined: Sep 08, 2019
Posts: 189
Location: Yorkshire U.K.
|
 Posted: Tue Dec 28, 2021 11:33 am Post subject: Fuel pump |
 |
|
Hi I have the correct military fuel vac pump on my M38. For a bit of fun I mounted a see through fuel filter so I could see the fuel flow through and was surprised how little fuel flows into and out, obviously enough as she keeps running.
So I connected the outlet on the pump to a pressure gauge and found it produced 4.5 PSI which according to TM 9-8012 would be correct.
Then I applied pressure with my mouth to the pump outlet as I read you should not be able to blow down the line, again all good I could not.
The instructions on the pressure gauge said the pressure should hold on the gauge for a few minutes mine did not. Would this be a sign that all is not well?
The other point is that the arm on the pump does not pump the fuel up into the little filter which would be handy as it would save cranking if she is left a couple of weeks and she needs petrol into the carb.
The more gauges you have the more things to worry about. Would the fact the pump arm does not work have any connection with the pump not holding pressure?
_________________
1952 M38 |
|
| Back to top |
|
 |
4x4M38
Member
Joined: May 30, 2014
Posts: 3444
Location: Texas Hill Country
|
|
| Back to top |
|
|
4x4M38
Member
Joined: May 30, 2014
Posts: 3444
Location: Texas Hill Country
|
|
| Back to top |
|
|
horse
Member
Joined: Sep 08, 2019
Posts: 189
Location: Yorkshire U.K.
|
| Posted: Wed Dec 29, 2021 10:33 am Post subject: |
|
|
Hi Brian.
I have fitted it as a temporary measure between the fuel pump and the carburettor. I understand that it will not be full of fuel other than if the filter was becoming blocked.
At least it showed me that the lever on the fuel pump was not working.
Are these fuel pumps supposed to hold pressure for a few minutes after shut down or is that for for modern units?
Thanks. Jonathan
_________________
1952 M38 |
|
| Back to top |
|
|
4x4M38
Member
Joined: May 30, 2014
Posts: 3444
Location: Texas Hill Country
|
| Posted: Wed Dec 29, 2021 6:37 pm Post subject: |
|
|
Hi Jonathan,
I don’t know about holding pressure.
Where I’ve normally seen the glass filters installed is usually between the tank and pump. The filter inside the tank is upstream of the pump also.
I have no idea if it makes any difference.
Your lever should prime the bowl on the carb. That’s the reason for it.
I know you have to get everything aligned correctly during assembly. Take a look at the diagrams. Maybe something wasn’t put together just right.
Weird I have two posts. I hit submit twice by accident but deleted one. I looked back. It was gone. Now it’s back.
_________________
Brian
1950 M38
MC11481
http://www.willysmjeeps.com/v2/modules.php?set_albumName=album372&op=modload&name=gallery&file=index&include=view_album.php |
|
| Back to top |
|
|
horse
Member
Joined: Sep 08, 2019
Posts: 189
Location: Yorkshire U.K.
|
| Posted: Thu Dec 30, 2021 10:22 am Post subject: |
|
|
Hi Brian.
Strange things sometimes computers.
I do have a spare rebuilt pump from Greece and the handle on that is much firmer, so when time I may do a swap.
The gaskets on the rebuilt pump looks like a leather type material but when I asked the supplier he said it was not.
In the meantime I am keeping an eye on the clear filter, after two days standing no drop in the amount of fuel in the bowl. I will see after a week at work.
Jonathan
_________________
1952 M38 |
|
| Back to top |
|
|
|
Forum FAQ
Search
Usergroups
Profile
Log in to check your private messages
Log in
