low back pressure? Help Please!!!

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sniper_boy309

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ok guys i just replaced my last muffler box with a hot dog on my d22 3.2L diesel navara.....every morning it seems like it floods itself... takes a while to start...it didnt do this with the stock exhaust....any ideas?
 
We used to stick hot dogs up car mufflers many years ago, some would smolder in the pipe and fall out while others would shoot clear across the street and splatter on shop windows (sorry Dandenong shop owners) but I'm guessing that's not the kind of hot dog you are talking about.
 
atmo or turbo?

even on an atmo it should make no difference. i would imagen the backpressure at such low revs would be nothing anyway.
did you have the battery off when welding?
is it mechanical or efi injection?
 
Won't be related, you most likely have another problem, follow Tweaks advice, he's the expert on all things mechanical.
 
+1.

We need a little more information.

Apart from Tweak'e's questions...

1) Is there any smoke once the thing starts, and if so what colour?

2) Does the engine crank over at a healthy pace or does it seem to groan a bit?

3) What happens if you get the thing started, run it for about 15 minutes driving around, then stop, shut it down and try to start it again? This could be a sign of faulty glow plugs or the associated circuitry.

4) How's that air filter?

5) Have you bought fuel from a tiny servo recently, or do you use truck stops?
 
ok i welded the exhaust off the ute then bolted it back up.......it mechanical tweake qd32 non turbo...once it starts it blows a light greyish smoke cloud and little bits of carbon...it cranks at good pace(brand new starter and battery)...only happens on first start e.g overnight, starts fine when turned on then off just worried as it didnt do it when the stock exhaust was on...i always use truck stops more turnover= fresh diesel :)
 
It could be air in the fuel line too, did you do a filter change? Using old seals or getting the new seal slightly wrong can cause air to get in and the bubbles are right buggers to get out.

Next time you're going for a cold start, try squeezing the primer bulb until it's firm BEFORE you attempt to start it. If that makes it start faster, you've got an air leak.

If there's no change, then I'm going with glow plugs.
 
try double glowing it, just to test.
i don't recommend double glowing but i think theres been a few comments on those motors being a bit hard to start and there is different glow systems for them.

it could be possible the increase in flow is leaving less air in the cylinder and its not getting enough heat under compression. or lack of end gas which would normally keep the cylinder warm.

be interesting to do a test, get someone to block the exhaust as you start it and see if it starts better.
 
ok primed it up still took alot of winding to even get smoke flowing out the back.....blocked it off and tried starting it as well but no real difference
 
tweak'e would this theory be possible im thinkin glow plugs because the stock exhaust retained more end gas to keep cylinder warm the glow plugs didnt hve to heat much on start up?
 
Has it lost power ?

Checked the glow plugs to see if there good ?

Injectors might need rebuilding, when you say flooding it could be dribbling fuel in over night.

Dave.
 
na no power loss that ive noticed.....wierd thing though dave it didnt have this probem bwfore i changed exhausts.....hence why im thinkin not enough heat in cylinders
 
Being a indirect mechanical injected motor the motors are designed to run on older grade fuel.

No computer means the timing etc on the pump has to be manually set, usually every 100,000km's in a mechanical injected motor is ideal to get the pump tuned.

In the injection pump there is a banjo filter (Little gauze filter) that goes in the fuel line from the tank. After a while they get blocked, might be worthwhile.

The injectors couldn't hurt with a rebuild either or new ones, there not that expensive for the mechanical motors.

Some of the CRD injectors are $900 each so I here and injectors for my ZD30 are $200 each genuine Zexel.

So dont feel to bad.

Prevenative maintenance is always a good thing.

Dave.
 
shouldnt make any difference...

with my cruiser, old 4.2L NA indirect injection, went from a full 2 1/4 system with muffler down to extractors with a 2.5 pipe running twin resonators and i got more power and no starting issues or heat issues
 

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