Diesel Fuel Injection System Help Desk

**Fiel** · October 3rd, 2011 03:54 AM

Grace & peace from God our Father & the Lord Jesus Christ...

Sir Dieseldude,

Sinubukan ko po na mag-reply sa thread na ito at kung sakaling mapansin nyo po,
nais ko po sanang humingi ng favor bagaman di ninyo ako kakilala...

God willing, I'm planning to study diesel mechanics by next year after my stint as an OFW,
samantalahin ko po yung scholarship program ng OWWA-TESDA, tagal ko ng nais mag-aral ng
automotive technology...

Kung loobin po ng Dios na maging certified na mekaniko ako ay simple lang naman po ang
pangarap ko: to provide everything I learned for free to anyone na nais na magtanong or
magpagawa sa akin in the near future...

kuntento na po kasi ako sa buhay...

May posibilidad po kaya na mabigyan nyo ako ng internet link or PDF or any document format
regarding sa engine repair manual ng Mitsubishi Fuso 4dR7? Nais ko po sanang magsimula ng
theoretical application sa engine na ito...

Sir Dieseldude, pagpalain po kayo ng Dios sa inyong mga endeavors...

Lubos na gumagalang,
Fiel

"The Lord bless you and keep you;
The Lord make His face shine upon you, And be gracious to you;
The Lord lift up His countenance upon you, And give you peace."
~ Numbers 6:24-26

**Dieseldude** · October 3rd, 2011 02:19 PM

Hello Fiel,

Gusto sana kitang tulungan, pero wala akong source ng information para sa 4DR7 engine. Nag surf ka na ba sa web? Medyo luma na ang 4DR7. Kung gusto mo magtrabaho as OFW, payo ko ay aralin mo na ang mga bagong common rail diesel engines dahil ito ang makikita mo dito o sa abroad

Godbless din...... Dieseldude

**ekfinder** · October 7th, 2011 08:44 PM

Sir Dieseldude,
I would like to ask some advice regarding sa Fuego ko 4jb1t ang engine.Almost every morning nag prime pump ako kasi laging may hangin yung fuel lines so shaky ang idling and nagstastall pero always sa first start of the day after nun ok na at ganda na manakbo all day.Heres what I already did I borrowed the hand prime pump from friends fuego still the same.Checked fuel tank for holes in the lines all looks ok.Replaced fuel filter today still waiting for results tomorow morning and also replaced transparent hoses just to see where air bubbles comming from.I can see some from the IP pump. and filter. Thank in advance for your help.

**ekfinder** · October 8th, 2011 08:24 AM

Update po new fuel filter did not work still the same. Additional info pagstart sa umaga mga 3 mins to 5 mins everything is normal.Then manginginig na yung engine at pagnirev mo di na kaya mag idle at mamatay.kailangan ko nang ipumpprime para magnormalize yung idle that happens only if it sits overnight.The engine has no visible smoke and still performs well. Thanks again

**Dieseldude** · October 8th, 2011 01:41 PM

Originally Posted by ekfinder

Update po new fuel filter did not work still the same. Additional info pagstart sa umaga mga 3 mins to 5 mins everything is normal.Then manginginig na yung engine at pagnirev mo di na kaya mag idle at mamatay.kailangan ko nang ipumpprime para magnormalize yung idle that happens only if it sits overnight.The engine has no visible smoke and still performs well. Thanks again

Your troubleshooting procedure is correct. Do you still see a large amount of air in the transparent hose between the new filter and injection pump at first start in the morning? And is air present in the hose after priming and after engine performance normalizes? What is your car's mileage?

**ekfinder** · October 8th, 2011 08:30 PM

Originally Posted by Dieseldude

Your troubleshooting procedure is correct. Do you still see a large amount of air in the transparent hose between the new filter and injection pump at first start in the morning? And is air present in the hose after priming and after engine performance normalizes? What is your car's mileage?

Yes I still see a bubble usually settling in the filter outlet in the morning between new filter and injection pump.Yes air is present in while the idling is normalizing its like small bubbles from a sprite softdrink.As for the mileage 94k just got it 3 weeks ago not sure if its accurate cause ill be the third owner.its a 03fuego by the way. Thanks for your time.

**ekfinder** · October 9th, 2011 10:05 AM

update po ulit i can see bubbles coming from the filter to the injection pump while revving the engine to normalize its idle in the morning the bubbles are small like a pea size and some times 3/4 inch in lenght it appears mostly in between filter and injection pump hose while revving the engine.

**Dieseldude** · October 9th, 2011 09:27 PM

Originally Posted by ekfinder

update po ulit i can see bubbles coming from the filter to the injection pump while revving the engine to normalize its idle in the morning the bubbles are small like a pea size and some times 3/4 inch in lenght it appears mostly in between filter and injection pump hose while revving the engine.

Is air still present after running the engine for approx. 5 minutes?

Try this too. Transfer the transparent hose between the suction side of the filter and the pipe from the fuel tank. This pipe ends near the fuel filter. If air bubbles are still present, you have a vacuum leak somewhere on your suction line from fuel tank to the end of the pipe.

**ekfinder** · October 10th, 2011 07:53 AM

Yes some air is still present.This morning i noticed where the problem starts after revving the engine I can see foam like bubbles coming from the injection pump fuel feed line (ip side)going up back to the filter and idle becomes shaky and stalls at times right after that.I have the tranparent hose also from the fuel tank line to the prefilter to filter and injection pump. Im beginning to think my ip has the problem because of the foam likebubbles coming from the fuel feed line after revving prior to engine shakes/stalling.my ip must be leaking and getting air overnight?not sure first time to encounter a problem like this. I will have it checked soon. Thank for your help sir.

**Dieseldude** · October 11th, 2011 11:52 AM

Originally Posted by ekfinder

Yes some air is still present.This morning i noticed where the problem starts after revving the engine I can see foam like bubbles coming from the injection pump fuel feed line (ip side)going up back to the filter and idle becomes shaky and stalls at times right after that.I have the tranparent hose also from the fuel tank line to the prefilter to filter and injection pump. Im beginning to think my ip has the problem because of the foam likebubbles coming from the fuel feed line after revving prior to engine shakes/stalling.my ip must be leaking and getting air overnight?not sure first time to encounter a problem like this. I will have it checked soon. Thank for your help sir.

You may be right about a possible injection pump problem. We were just trying to diagnose all possibilities before considering injection pump repair.