• Advertisement

fuel pump for 31p707

Use this forum to discuss small engines, and the equipment or machinery that they power. This is the main section for any technical help posts and related questions.

fuel pump for 31p707

Postby 38racing » Thu Jun 15, 2017 3:39 pm

ipl has a before 08... and after 08.. my daughter's is 04. early pump is 72$ .later is 30$ .oem I assume. later AM I can get for $13. don't see AN for early.wondering why the later wouldn't work on the 04. we seem to have oil loss. valve cover is definitely one source. didn't we have a thread on oil loss via fuel pump impulse?manometer showed crankcase vacuum and oil no oil in the air cleaner and no smoke so head gasket seems ok.
38racing
Forum Pro
 
Posts: 2287
Joined: Thu Nov 07, 2013 10:12 pm
Location: Ontario Canada

Advertisement

Re: fuel pump for 31p707

Postby bgsengine » Thu Jun 15, 2017 4:12 pm

Both being the round pancake fuel pump? no difference I can see except one (more expensive) version was riveted to a metal plate for mounting. later models were bolted on - Probably could drill out rivets and re-use the old metal plate with a couple self-tapping screws Pumps are the same, just one comes with a mounting bracket. I assume that was legacy from the older rectangular walbro pumps (which were actually rebuildable) they used to use.

as for oil loss you are thinking of a ruptured fuel pump diaphragm leaking gas into the oil causing oil loss, more likely That, or impulse hose or fitting leaking oil out.
How poor are they who have not patience. What wound did ever heal, but by degrees? - Iago (Othello Act II, Scene 3)
bgsengine
Briggs MST
Briggs MST
 
Posts: 3296
Joined: Sun Nov 03, 2013 10:07 pm
Location: Northcentral P.A.

Re: fuel pump for 31p707

Postby KE4AVB » Thu Jun 15, 2017 4:58 pm

as for oil loss you are thinking of a ruptured fuel pump diaphragm leaking gas into the oil causing oil loss, more likely That, or impulse hose or fitting leaking oil out.

Could also be leaking out the fuel pump vent itself too. I have this seen on a 21hp on Cub ZTR.

With today's oils don't on count it smoking. I had one two years ago that was burning a qt of oil per half acre of mowing, I could only smell oil burning; no smoke at all. If you got oil in the air cleaner I say that the head gasket is leaking between the cylinder and the push rod galley over pressurizing the crankcase and 310000 are prone to blowing head gaskets too.

To determine if it is the head gasket or not on that OHV pull the valve cover and do a leak down test. If you hear escaping air sound louder at the push rod galley then any where else I would say the head gasket is blown. Remember to lock cylinder at 1/4 pass tdc compression.
The truest measure of society is the how it treats its elderly, its pets, and its prisoners.
User avatar
KE4AVB
Forum Pro
 
Posts: 5999
Joined: Mon Nov 04, 2013 11:23 am
Location: TorLand

Re: fuel pump for 31p707

Postby 38racing » Thu Jun 15, 2017 7:35 pm

original post should read 'no' oil in the air cleaner
38racing
Forum Pro
 
Posts: 2287
Joined: Thu Nov 07, 2013 10:12 pm
Location: Ontario Canada

Re: fuel pump for 31p707

Postby KE4AVB » Thu Jun 15, 2017 7:43 pm

38racing wrote:original post should read 'no' oil in the air cleaner

Original Post Corrected then.
The truest measure of society is the how it treats its elderly, its pets, and its prisoners.
User avatar
KE4AVB
Forum Pro
 
Posts: 5999
Joined: Mon Nov 04, 2013 11:23 am
Location: TorLand

Re: fuel pump for 31p707

Postby 38racing » Tue Aug 22, 2017 7:56 pm

bgsengine wrote:Both being the round pancake fuel pump? no difference I can see except one (more expensive) version was riveted to a metal plate for mounting. later models were bolted on - Probably could drill out rivets and re-use the old metal plate with a couple self-tapping screws Pumps are the same, just one comes with a mounting bracket. I assume that was legacy from the older rectangular walbro pumps (which were actually rebuildable) they used to use.

as for oil loss you are thinking of a ruptured fuel pump diaphragm leaking gas into the oil causing oil loss, more likely That, or impulse hose or fitting leaking oil out.



Finally bought the $13 aftermarket pump and it looks like the one on the engine and even has the steel mountin bracket on it.
38racing
Forum Pro
 
Posts: 2287
Joined: Thu Nov 07, 2013 10:12 pm
Location: Ontario Canada

Re: fuel pump for 31p707

Postby 38racing » Mon May 14, 2018 4:54 pm

updating . still seemed to use oil with new pump.
they got mower out and ran an smoked and stopped. just replaced the head gasket this morning. blown in the classic fashion. opening a thread on her neighbour's.
38racing
Forum Pro
 
Posts: 2287
Joined: Thu Nov 07, 2013 10:12 pm
Location: Ontario Canada


Return to Technical Discussion Forum

Who is online

Users browsing this forum: No registered users and 5 guests

cron