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Hi Guys, i have recently purchased a t4 2.4 aab, i think i was sold a green lemon but am perservering with it. The tensioner went on the cambelt, resulting in a £580 new head, plus £150 gasket and new stretch bolts and alot of time, Its now back together and timed as supposed to be. A little flat when reving so i advanced the diesel timing a tad and it seems ok. The only issue know is when driving under load the engine sounds very tinnie, almost like pinking. The noise is worse at high revs. I have checked the crank timing to the camshaft, everything is 100% aligned. the pump timing could do with pulse adaptor setup, but i wouldnt think that is what is causing the noise. There were valve marks on the pistons when i removed the old head, the engine looks like it had been in bits before i replaced the head recently, very loose and missing bolts, cross threaded engine mount also not tighten fully up. Do you think that the big ends could have gone due to the valve marks on the head? All help will be gladdly appreciated. I want to keep it so its worth spending the money to get it right, thats just the way it goes sometimes. Many thanks
 

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Given what you have said, it may not be this, and i'm not really an expert, but have had experience with something similar to this, so will share it anyway, i'm sure a real mechanic can help better, as above T:

I had done a similar job to you on an early 93 AAB, and the head for me was pre-assembled that i replaced, however the tapping noise i get now is the vac pump, this can be confirmed by pumping the brake pedal, and sound goes! Common 2.4d problem i believe.
 

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Do you think that the big ends could have gone due to the valve marks on the head? All help will be gladdly appreciated. I want to keep it so its worth spending the money to get it right, thats just the way it goes sometimes. Many thanks
Big Ends are on there way out , if the noise increases with revs i would say that's the cause :(

Drop the sump and check the big ends, it may not have damaged the crank yet if your lucky so you will get away with changing the Big Ends and running it in again. T:

If the Crank journals are marked then it crank re grind time :mad:
 

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Is a bell like ringing noise or more like a knocking noise ? If more like a ringing noise I had same on mine check as said above coz it sounds like vacuum pump may be going,if more like a knocking sound then big possablity big ends :( then yes change your big end bearings ASAP so as not to damage your crank coz that'll be loads of ££££££'s
 

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Discussion Starter · #6 ·
hi guys, thanks for your help so far, yep a knock was loud, fitted new vac pump and also vac pump push rod at same time. big clatter went away. one problem fixed. Now, its starts fine, a little clangy when using cold start. But when you drive it noise is when you let off after accelerating, like a real wirl noise. not gear box, its more like a vibration niose as if something is loose. but all it tight under the van. It defo is coming from the engine. I have aligned the crank to a 0 on the flywheel, but some people contratict this and say use the line not the 0. can anybody shed light on this. Also if it was big ends, i would of thought they would knock at low revs and little ends would knock at high revs. All your guys help is really appreciated. Many thanks guys.
 

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. Also if it was big ends, i would of thought they would knock at low revs and little ends would knock at high revs. All your guys help is really appreciated. Many thanks guys.
No when its your big ends , you may get no knock at idle but when you increase the revs the knock increases . When it sounds like that its the Big Ends. :(
 

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"A little flat when reving so i advanced the diesel timing a tad and it seems ok. "

Really? You know that the cold start advances the injection timing don't you? Sounds to me like your over advanced.

//NiSk
 

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To check if its BigEnds or LittleEnds you could change tho oil to a more viscous one.....20W50....If the noise decreases or disappears completely, then that's your problem.
If the noise doesn't change it's something else.

Might be a rattling clutch bearing......does it stop when you press the clutch?
Hydraulic tap lifters....twice I have taken them out by now, but never filled them with oil when put them back.
I did take them apart and cleaned them thoroughly, then put them back empty of oil, and after starting the engine in few seconds (5-10), I had no noise from them anymore.
If you did not take them apart and cleaned them....they could give you that noise.
Take your alternator belt OFF...might be alternator bearings.
Same with steering belt.

If everything fails to disclose the source of noise....buy some noise insulation and wrap your engine bay in it.
Keep driving until something dies...and that's your problem.
 

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They would get solid if the gunk in them would obstruct the little orifice, and the oil won't flow through anymore.
But they are....hydraulic.
Clean them well.....20 min job (after you removed the camshaft).
 

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EH !!!!!!!!!!!
How can they have solid litfers?????
If they did there would need to be some sort of manual adjustment for valve clearance.
DEFFO got hydraulic lifters
Hmmm interesting , did you work the cam and tappets prior to fitting the head ?

must have had them changed

Mine Has solid bucket tappets :eek:
 

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dude if u got wirling noise it might be power steering pump as mine makes that sort of noise.but as brookster said at idle u won't get any knocking it's only at revs ur big ends start knocking and boy do they knock :eek: also check ur belt pully is ok as this can give off a wirling noise if it's on it's way out,best of luck an good hunting freind T:
 

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parts code prefix: 074, ID codes: 3D, AAB, AAS, ACP, AJA

cylinder head & valvetrain cast aluminium alloy; two valves per cylinder each with two concentric valve springs, 10 valves total, solid bucket tappets, timing belt-driven single overhead camshaft (SOHC)


engine configuration & engine displacement inline five engine (R5/I5); 2,370 cubic centimetres (144.6 cu in); bore x stroke: 79.5 by 95.5 millimetres (3.13 in × 3.76 in), stroke ratio: 0.83:1 - undersquare/long-stroke, 474.1 cc per cylinder, compression ratio 22.0:1
 

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Can't understand that????????
How did you adjust your valve clearances????????
In automobiles, shims are commonly used to adjust the clearance or space between two parts. For example, shims are inserted into or under bucket tappets to control valve clearances. Clearance is adjusted by changing the thickness of the shim T:
 
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