Bearing noise and Boosting Problems.

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ice_berg86

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Nov 6, 2015
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Plainlands QLD
Hey guys,
Been on here for a little while now, first time posting.

I bought a D40 in mid december last year and all has been well until a couple of days ago.

I have a noise coming from the front of the engine, it sounds like a bearing in the pulley / alternator. I'm yet to take the belt off to confirm but will do it this weekend.

The other problem i'm having is the car is making a sucking noise when accelerating and when its under load (i.e. going up hills with no increase in R.P.M). It seems to have more power and when going up the hill near home, before i had to rev the car a lot more to change into second. It now seems to be more constant instead of having no power until the boost kicked in at around 2000 R.P.M.

It also isn't blowing any smoke when driving up the toowoomba range (4th gear flat to the floor). Where as before, it would blow a bit of smoke and even more when it was flat to the floor.

I had a quick look at the intake pipes and i can't seen any leaks. Any ideas would be great.
 
So its got more power, running better and no smoke. So whats the issue? Did you check to see if there is a budgie in your snorkel?
 
You put it that way, i shouldn't be complaining. No snorkle, so i can rule out the budgie haha.

Just seems weird that both the bearing and and the induction noise happened at the same time. Last thing i want is something to break.
 
The idler pulleys (particularly the one near the alternator) are often a source of noise, but the belts can also make a racket and it's worth doing these two things to see if they are the culprits:

1) Use some dri-lube on the inside of the belt.

2) Spray some silicone lube in behind the little cap that covers the bearing in the idler pulley.

Induction noise could come from several sources. In my car, it appeared when the clips holding the side of my airbox in broke and the side started flapping. It could alo occur because of a leak in the EGR - you should be able to see black soot marks from a crack in the gold tube that runs around from the exhaust manifold to the intake manifold.

Otherwise, it could be fuel. BP Ultimate Diesel is 55 cetane, which is higher than other brands. If you've just changed from Shell or Liberty/Mobil/Matilda/United to Caltex or BP that might explain the difference too.
 
I did just spray the belt with stop squeak and i also just filled up at local BP, normally I've been going to caltax. I'll check that pipe but im pretty sure the bloke i bought the car off blocked the pipe off at both ends.
 
Caltex is 51/53 cetane so not hugely different. They supposedly have different amounts of detergent and antifoaming agents in them - funny, I found BP to be quite foamy. I can't speak for Liberty/Matilda/Puma etc because I haven't (and won't unless I'm completely desperate) bought from those suppliers but they usually (except maybe Puma) source their fuel from Mobil and some reports say they mix it at up to 20% with biodiesel.

Not that biodiesel is bad. Home-made could well be, sure, but commercial grade biodiesel has to be made so that it's at least as good as dinosaur or it wouldn't stand a chance at competing.
 
Just out of left feild, but it *could* be your EGR tube has a small split it in - or if you have an EGR block, it's not sealed at the engine entry end. These whistle at odd moments, particularly when the EGR valve is open..

Make sure there is no leaks, and the bolts holding the EGR pipe are well secured..
 
So i filled up at the normal caltax i use and i still have the same problem. I checked the EGR tube and it looks good, it has been blocked off at both ends so it shouldn't matter anyway. Both connections look solid.

There seems to be a bit of oil spray from the pipe between the turbo and the intercooler, closest to the motor.

The whistle / suction noise is only when the motor is boosting.

I'm going to the mechanic next to work to take it for a drive and see what he thinks.
 
Id say you have a boost leak. Remove, clean, refit tight all your boost hoses from the Hot side to the throttle body..

You'll need to take the front grill off to get to the one between the in and out of the intercooler.
 
So I took all the pipes off, checked and refitted them. I couldn't find any leaks and all the connections were pretty tight. A bit of oil in the pipes, so i might need a catch can.

I took the belts off and it took it for a quick drive and the noise is still there.

I'm thinking the intercooler might have a crack in it (the only thing I can think of), but I'm not sure how you would check it ?
 
If the intercooler has a crack in it, look for oil spatter / leak on external fins.

Given the amount of heavy breathing these YD25's do, it's fair to say your intercooler would be well caked in oil - or any leak would be a site of oil.

Id your hot pipe baffle well sealed? No sign of any external oil over any of the pipes? Your airfilter box sealed, and no cracks / open holes in the turbo intake?
 
Turns out it was a leak in the hot pipe just after the turbo, oil spray on the engine cover gave it away. Ordered a new hot pipe from plazmaman and it's working better than ever. More responsive from take off and going up hills.
 

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