Air-lock in fuel lines

[Rick NZ Member Find all posts View Profile Close Rick NZ]

Again just guessing not diagnosing the problem
There may be more than one air leak.
Clear hoses are the only way to ensure ALL air leaks are found

[Rick NZ Member Find all posts View Profile Close Rick NZ]

Lol I'm not worried , my 120 runs fine

My comments were based on my findings, with my 120 and 3 hilux's I have found with air leaks at the OEM plunger
Indeed more than likely bypassing the Donaldson will sort the noted problem
However eliminating all of the air leaks ( which most owners don't even know they have ) does a world of wonders for the 1KD
Smoother running, quieter engines and better throttle response

Rick

[Riv39 Advanced Member Find all posts View Profile Close Riv39]

Rick, when you say 'quieter engines' with no air leaks what do you actually mean. What noise is created by air leaks?

[Rick NZ Member Find all posts View Profile Close Rick NZ]

less engine noise in general

less diesel rattle has been noted on all vehicles
Ive even had 2 of the 3 customers call me and say how much quieter the engine is

unsure if the air being compressable is causing unstable/ irractic fuel pressure in the rail

I have a data log of the fuel rail pressure dated- 2months ago - thinking about it now, maybe I'll do a comparison

[mackayvx Advanced Member Find all posts View Profile Close mackayvx]

So mick it been 6 days!!!
How the car starting???

[mackayvx Advanced Member Find all posts View Profile Close mackayvx]

Im thinking mick must have sorted his problem.
Would have been good to know the outcome.

[Mick70 Junior Member Find all posts View Profile Close Mick70]

Apologies for the very delayed response.

This where I'm at- the problem went away when I by-passed the Donaldson, as predicted by a few, so I now know the cause. I've contacted Donaldson and was informed that there are 3 possibilities for why it could be sucking air. The threads, and one of two gaskets in the unit. I haven't gotten around to it as yet but I want to have another crack at reinstallation before abandoning the idea, paying particular attention to those 3 vulnerabilities.

On the recommendation of a few, I'm also thinking of installing a small, online fuel pump at the tank just to compliment the OEM pump and the engine. My thought is that maybe the "drawing" pump is having a little trouble dragging fuel through two filters. Worth a shot I guess as it can't hurt and won't cost much to do.

[matt150 Avid PP Poster! Find all posts View Profile Close matt150]

Forget wasting cash on a 'extra' fuel pump. Get to a decent mechanic, not the bloke that installed the second filter arrangement. Explain the issue and have the Donaldson filter set up pulled out, all the fittings sealed correctly with thread tape and then all refitted. The problem is air, the cause is a rough mechanic.

Anyone telling you that you need an extra fuel pump has no idea.. Run away....Been doing this diesel doohickery shit for a while now and they won't compress and fire on straight air !

[raydes Advanced Member Find all posts View Profile Close raydes]

air lock

why it could be sucking air. The threads, and one of two gaskets in the unit................ as I previously said check the seals thickness. You can put a new filter in with one of the "3 " seals supplied ,every thing feels ok with the bolt through the middle tight but its not compressing the seal and draws air in. The top of the filter touches the top housing in the middle and the outer edge of the filter does not seal on the rubber seal.

[Mick70 Junior Member Find all posts View Profile Close Mick70]

raydes- I do remember your previous post and it's been noted, mate. Thanks for your input.

Matt, I'm no mechanic and I'm just trying to feel my way through the dilemma. Leaks aside, I think the additional fuel pump was recommended as to aid the oringinal but I see your point and wondered the same myself- hence why I made mention of it. Thanks

[cfryback Find all posts View Profile Close cfryback]

Just putting this out there - what is your CRD pump like, has it been tested?

I myself with my engine re-build got a reconditioned pump.

[Mick70 Junior Member Find all posts View Profile Close Mick70]

Never had it tested to be honest so I don't really know. The donk still idles a little rough though, at the lights and when cold, even before I had the second filter installed. Does so even when I've primed till the plunger goes hard. As a process of elimination, I might look at getting the plunger replaced at the next service. Though this I can live with, just glad I've sorted (for now) the air lock issue. A big thanks to all who have put forth suggestions with a view to helping me solve the issue. Legends!

Much appreciated,
Mick