hj 45 fuel feed pump strange mistery connection

[tornio]

Hello guys, looking for a possible source of air into the fuel circuit I noticed that my lift pump (feed pump) is connected the wrong way: in the manuals and photos I have seen here on the site, the inlet is towards the tank and the outlet towards the radiator with a metal tube that carries the diesel to the filter... as you can see in my vehicle it is the opposite... I am confused... on the other hand, everything seems original..... the truck run....

from this site like factory manual

thi is mine you can see the inlet (yellow circled) , the outlet red circled ...?????....

also this pipe (copper i believe) seems factory

but the pipe that goes from the feed pump outlet to the filter is not all hard line as you can see while from the filter to the pump it is hard line as per the manual

very very strange ...

has anyone already seen an assembly like mine ?

what the copper pipe does?

i see that also the priming pump is on the right of the housing and the check valve chamber plug is on the left ...
Even though this seems logical to me, after all the engine runs ...
I have my doubts that perhaps this feed pump is not a Toyota derivative but maybe a Mercedes or something else, after all it's a Bosch style.

every piece of advice will be greatly appreciated

 

[duncanrm]

I like your theory that the feed pump was from a different vehicle. Anyone know if the B/3B engines feature a feed pump that has inlet/outlet reversed for operation on the left hand side of the engine?

 

[tornio]

hi duncanrm, my 40 and my 42 all have inlet toward the tank and outlet toward the filter...
but if the feed pump is from a different vehicle why the copper tube seems factory ?

 

[tornio]

i discovered these photo :

this is my 45 when the PO did the camper conversion (1996)

and this photo before conversion

you can see that there was the same hose/pipe orientation

but this was in the 1996 ... the truck is an 1976 so there is no warranty that the feed pump was factory....


i'm confused...

 

[duncanrm]

I really do feel another lift pump from a different vehicle has been used and the system replumbed.

I've never seen a factory copper pipe like that on a Toyota diesel

Those photos are very cool, so nice to have some history on your vehicle.

 

[tornio]

What do you think the copper tube is used for?
at that point it should be the air bleeder.... black circle , at this point i think that i can cut / delete this tube and the connection at feed pump inlet ...

By any chance, do you know what the yellow circled piece means or what it is for?
THE FSM call it injection pump cleaner ... ?

 

[duncanrm]

All odd.. they do appear to have plumbed the pump body bleed point back to the inlet of the lift pump.. the 12HT had this done from factory. I do feel you can delete it without issue.. but you'd need to reseal the bleed point somehow.

I think you are right to be suspicious of all that non standard fuel plumbing.

For sucking air, here's my checklist for the 2H..

2H - Sucking Air/Fuel Restriction

docs.google.com

 

[tornio]

By any chance, do you know what the blue circled piece means or what it is for?
THE FSM call it injection pump cleaner ... ?

 

[duncanrm]

By any chance, do you know what the blue circled piece means or what it is for?
THE FSM call it injection pump cleaner ... ?

I am not entirely sure what that is..

If the lower part of the pump doesnt have an engine oil feed (like the 2H pump) I am wondering if its some kind of breather.. some of the earlier B series pumps that didn't have an engine oil feed had a dipstick to check the oil level in the pump.. have you opened it up?

 

[LDRF]

What do you think the copper tube is used for?

For plumbing the ice maker?

I wouldn't expect any copper tubing in a factory engine. That would be backyard/shade-tree mechanic stuff. It's been working for, at least, 29 years, so you'll probably want to keep it. You can always try to tighten the banjo fittings and/or open them up and tighten them down, if you suspect an air leak at the connections. There may be copper washers that you may need to replace if you open it up.

 

[tornio]

If the lower part of the pump doesnt have an engine oil feed (like the 2H pump) I am wondering if its some kind of breather.. some of the earlier B series pumps that didn't have an engine oil feed had a dipstick to check the oil level in the pump.. have you opened it up?

yes i know it , my 40 has this earlier b engine
on the 45 I changed the oil of the pump a little while ago.

I know your documentation about air problems and the others , GREAT WORK
THANK'S to share

for the air , i have a lot of copper whasher and i bought the primer pump because I suspect that it is the cause....
I changed the hose from chassis to lift pump and the hose from lift pump to filter so this section would be fine
to be honest when i replaced the fuel filter that is the old immersion style i had to disturb one of the two banjo and i didn't replace the whasher...
so my plan is :
1 replace the whasher and the "o-ring" at the filter air bleed
2 replace the primer pump
3 tighten a little the banjos
4 install a new hose from tank straight to lift pump then install a transparent hose from lift pump to filter to see if there is air
if there is no air install a new hose from tank to chassis hard line to check if this line is ok
5 because my plumbing from lift pump to filter is not factory I think of modifying it like the bj40/42 : banjo with hydraulic hose crimped

have a good day!

 

[tornio]

I wouldn't expect any copper tubing in a factory engine.

yes there is no evidence in any manual but probally this tube is not the cause of the problem