3126 HUEI pump replacement

[jhanan]

Originally Posted by wb7auk

Try 18,000 to 30,000 lbs

I found this article:
HEUI Injectors

The fuel pressure is up there at 26,000 psi, but the oil pressure behind the injector is 3000 psi...not that this is any authority on the topic.

[wb7auk]

High Pressure Oil Supply Pump:
The hydraulic supply pump is a seven-piston fixed
displacement axial piston pump. It raises the system's oil
pressure level from typical engine operating oil pressure
of 40 psi to the actuation pressure required by the
injectors of 870 to 3300 psi. During normal engine
operation, pump output pressure is controlled by the
Injector Actuation Pressure Control Valve (IAPCV) which
dumps excess flow back to the return circuit. Pressures
for specific engine conditions are determined by the ECM.

Copy from Cat Manual

[wb7auk]

Originally Posted by jhanan

I found this article:
HEUI Injectors

The fuel pressure is up there at 26,000 psi, but the oil pressure behind the injector is 3000 psi...not that this is any authority on the topic.

You are correct I mixed up fuel injection pressure with oil pressure

[wb7auk]

The HEUI injector is hydraulically actuated by high pressure
engine oil supplied by the high pressure oil pump. It consists of
four major components:
1. Solenoid:
The solenoid is a very fast acting electromagnet which,
when energized, pulls the poppet valve off its seat.
2. Poppet Valve:
The poppet valve is held on its seat by a spring. In this
closed position, high pressure inlet oil is blocked and the
intensifier cavity is opened to drain. When the solenoid is
energized, the poppet is quickly lifted off its seat. The path
to drain is closed and the inlet for high pressure oil is
opened.
3. Intensifier Piston and Plunger:
When the poppet valve opens the inlet port, high pressure
oil enters the injector and acts on the top of the intensifier
piston. Pressure builds on the intensifier, pushing it and
the plunger down. The intensifier is six times larger in
surface area than the plunger, providing six times
TL960 SERVICE MANUAL
Page 13-15
multiplication of force. The downward movement of the
plunger pressurizes the fuel in the plunger cavity, causing
the nozzle to open. Thus 3,000 psi oil provides fuel
injection pressures of 21,000 psi.

[bigdog]

Good Grief,but $2K sounds awfully high for labor. It is amazing as to how much these shops will try to get away with. There is a shop here in our area that was highly reccomended to me for some engine work. I took it out there and the first thing he told me was that I needed a new engine at about $16-20K for a rebuilt installed. $13K for the engine shipped from Portland and the rest was installation. I looked up the engine and one from Kentuckey was $4K plus shipping,but no cost for shipping the core back. The one from Portland was $7K and was almost a complete engine and they had one available if I wanted to come down and get it. Yes, I do have a friend that has a large enuff truck to haul it and would loan it to me and the shop said no way is that gonna work. Turns out that I didn't need a new engine anyway..Only needed a new Heui pump.

[jhanan]

Originally Posted by bigdog

Good Grief,but $2K sounds awfully high for labor. It is amazing as to how much these shops will try to get away with. There is a shop here in our area that was highly reccomended to me for some engine work. I took it out there and the first thing he told me was that I needed a new engine at about $16-20K for a rebuilt installed. $13K for the engine shipped from Portland and the rest was installation. I looked up the engine and one from Kentuckey was $4K plus shipping,but no cost for shipping the core back. The one from Portland was $7K and was almost a complete engine and they had one available if I wanted to come down and get it. Yes, I do have a friend that has a large enuff truck to haul it and would loan it to me and the shop said no way is that gonna work. Turns out that I didn't need a new engine anyway..Only needed a new Heui pump.

How much was your HEUI replacement - parts and labor and who did you have do it, or did you DIY?

[firedoc]

C7 HEUI pump replaced 2 months ago by Freightliner in Pacific Washington. $1200 for pump, $1400 for labor.

[Dtwallace]

Don't intend to sound crude, but did you get a kiss with that bill???

[jhanan]

Ya, its 2600 job that's why might consider it as a DIY project - it depends how much work needs to be done on the injectors - it can easily work its way up to 5 to 7K.

[akeyzoo]

$2600 aint bad. One thing preventing DIY is a special tool to remove the hard line from the pump. Plus, there is that risk that you screw it up in your driveway and have to have it towed. blech...

Chris