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Is it mechanical or air in the fuel delivery?

Posted: Fri Jun 17, 2011 9:16 am
by progroup
Everything was going hunky dory until I changed the fuel filter for the first time since buying this vehicle. I was esxpecting some air to get into the system, so I bled the injectors [maybe not enough, not sure yet!]. The engine ran really well at 2,000 RPM for about a minute or so, then some major happened either machanical like spinning the timing belt [oh sh**t I hope not #-o ]. At least that is what it felt like. One of my heavy equipment mechanic relations suggested I rebleed each injector one after another. Some improvement in idle when cracking each injector pipe #1 through #4. But after several iterations, the same roughness exits.

Could it be that the belt slipped a notch? This is a brand new head, belt, tensioner, etc. Has anyone experienced this before :?: :?:

If some of you will post a response, I'll try first thing in the morning [Friday]. I hope there is a Bongo Mech out there in this forum who might help. Otherwise, all of you folks have contributed so much to me over the last few weeks. I have picked up so many good worthwhile tips!!!

My son asked me today... "is there a forum for every car in the world" to which I replied "Not likely son, but aren't we lucky to have Bongo Fury to turn to for help" :D :D

Re: Is it mechanical or air in the fuel delivery?

Posted: Fri Jun 17, 2011 10:06 am
by haydn callow
I have changed a few fuel filters and have never had to do anything other than "change the filter" .. no air bleeding or anything.....I have done it with and without filling the new filter with fuel before refitting.....the system bleeds it'self..
So
I doubt that is the problem..
As you have just had it all to bits I would suspect it could be the cambelt...carn't really think if much else.

Re: Is it mechanical or air in the fuel delivery?

Posted: Fri Jun 17, 2011 10:12 am
by progroup
haydn callow wrote:I have changed a few fuel filters and have never had to do anything other than "change the filter" .. no air bleeding or anything.....I have done it with and without filling the new filter with fuel before refitting.....the system bleeds it'self..
So
I doubt that is the problem..
As you have just had it all to bits I would suspect it could be the cambelt...carn't really think if much else.
My gut tells me the cam belt! This is the new aftermarket belt that came with the new head package. I did order a new cam kit from BongoBits, which I could put on after determining that's it. But why would this happen now? It ran beautifully all day and smooth.

Re: Is it mechanical or air in the fuel delivery?

Posted: Fri Jun 17, 2011 10:28 am
by rita
Hi progroup,

The system should be self bleeding,but this will depend on the state of the pump.If you suspect the fuel filter and you still have the old one try swapping them, and check the seal.The other thing,did you check the strainer on the pump.

Best of luck..

Re: Is it mechanical or air in the fuel delivery?

Posted: Fri Jun 17, 2011 3:31 pm
by progroup
Interesting; I haven't heard of a self bleeder fuel system in Diesels. :o

My guess is mechanical. But why? Inferior parts? BongoBits shipped me the Cam kit [Belt & Tensioner Bearing]. Peer Parts in London sent me a Belt with the head kit. I would pay more for Mazda or even Dayco.

Why did it run so well and then immediately after I change the fuel filter, which I did anticipate, it runs so rough you'd think the cam. :?

Re: Is it mechanical or air in the fuel delivery?

Posted: Fri Jun 17, 2011 3:37 pm
by widdowson2008
Waaaaaaaay out of my comfort zone here (seeing if it may relate to other recent posts) but........ does it sound as though it isn't firing on all cylinders?

Re: Is it mechanical or air in the fuel delivery?

Posted: Fri Jun 17, 2011 3:51 pm
by Northern Bongolow
could it be the new timming belt and spring has put more tension on the front end seal in the pump, and now its sucking air in.
has the oil level risen any since rebuild(fuel leaking from pump and filling the sump.)

Re: Is it mechanical or air in the fuel delivery?

Posted: Fri Jun 17, 2011 3:53 pm
by haydn callow
Have you cleaned out the gauze mesh filter under the banjo on the fuel pump (just a thought) worth doing that just in case you disturbed some crud changing the filter

Re: Is it mechanical or air in the fuel delivery?

Posted: Fri Jun 17, 2011 4:12 pm
by missfixit70
Worth checking the camshaft, 2 recent cases with posible similar sounding symptoms, hopefully not though [-o<
http://www.igmaynard.co.uk/bongo/forum/ ... t=camshaft
http://www.igmaynard.co.uk/bongo/forum/ ... t=camshaft

Wonder if an oilway is maybe blocked or something?

Re: Is it mechanical or air in the fuel delivery?

Posted: Fri Jun 17, 2011 5:51 pm
by widdowson2008
missfixit70 wrote:Worth checking the camshaft, 2 recent cases with posible similar sounding symptoms, hopefully not though [-o<
http://www.igmaynard.co.uk/bongo/forum/ ... t=camshaft
http://www.igmaynard.co.uk/bongo/forum/ ... t=camshaft

Wonder if an oilway is maybe blocked or something?
That's exactly what I was refering to earlier when I asked ......isn't firing on all cylinders. Didn't want to spell it out and frighten the hell out of progroup.

Re: Is it mechanical or air in the fuel delivery?

Posted: Fri Jun 17, 2011 5:57 pm
by missfixit70
You know me Steve, life's too short to fanny about hinting & sugar coating things :wink: Expect the worst & you'll never be disappointed :roll: :wink:

Re: Is it mechanical or air in the fuel delivery?

Posted: Fri Jun 17, 2011 6:10 pm
by widdowson2008
missfixit70 wrote:You know me Steve, life's too short to fanny about hinting & sugar coating things :wink: Expect the worst & you'll never be disappointed :roll: :wink:
Are you saying I fanny about? :shock: ...................................Yep, you're probably right :lol: .........AGAIN. :roll:

Re: Is it mechanical or air in the fuel delivery?

Posted: Fri Jun 17, 2011 7:52 pm
by 321Away
snapped camshaft in general is a real pain to get fired up, needs winding and throttle flat to the floor and then it wont usually rev over 1000rpm or so, as suggested take a look at the banjo filter in the pump, as long as you re-fitted the spring and bolt for the belt tensioner i cant imagine it jumping a tooth, try opening up the bleed pipe (not the header tank) and start the car and see if you get any pressurising/water spouting out of the pipe?

also try re-fitting the fuel filter, make sure its seated and sealing as it should, also have you tried just winding it and letting it chug for a while, if you run them out of fuel, like oyu have it takes a while for the system to bleed itself? try letting it run for 5 mins.

Julian

Re: Is it mechanical or air in the fuel delivery?

Posted: Sat Jun 18, 2011 1:50 am
by The Great Pretender
Air in the system can be a pain, the ECU can make it worse, try feeding it WD40. :wink:

Re: Is it mechanical or air in the fuel delivery?

Posted: Mon Jun 20, 2011 7:55 am
by progroup
Well guess what all... It's none of the above afterall! :x

The new head is/was defective. Closer inspection revealed a dropped rocker on #2 cylinder [the first of two times this would happen!].

I tried the easiest first of course by cracking each injector line at the head while running which caused severe roughness on #1,3,&4 but not #2.... interesting I thought!

I then removed the valve cover and discovered #2 exhaust valve rocker was floating loose having just popped out. So, I just put it back on and adjusted the rocker accordingly. I adjusted each other rocker in sequence according to what they should be set at.

Turns out that all the valves needed to be adjusted. The company I purchased from said no need to because the factory does this. Ya right!

Upon restarting, the engine ran better of course but funny, as the day progressed running the Bongo, the same thing happened again only this 2nd time the rocker split in two. I have pics of all this and will post later.

So, I replaced the broken rocker with a spare off the old head, and with the Bongo warmed up took off for another test drive. By the time I made it back to my shop, the engine was just starting to do the noise yet again. Something else still isn't right here!

Talking it over with a neighbour friend tonight, we agreed that it must be related to a bent exhaust valve. His advice was to remove the head again.

I am obviously going to suffer doing this work at the cost of my own work to pay

Tonight I am just providing a report to you the forum members about my progress. I will be calling my supplier in the morning to see what can be done in a jiffy considering I am located in BC, Canada.

Cheers,
Dave