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View Full Version : Need some clarification on head gasket & timing belt replacement



wclepse
08-02-2013, 05:56 AM
So a few months back I posted here that I was having a coolant leak at the flange on the back of the head. Well I never did anything about it because we were moving, it was cold and honestly I wasn't losing much fluid. Well last week while driving home the flange just let go completely. So I had the car towed to an indy dealer that confirmed the flange is done but also said my head gasket is leaking. But I guess he has gotten burned on these turbo'd cars and doesn't want to touch it since he thinks there will be other problems given the 220k on the clock. So I have two options...donate the car since I know I'll get nothing in a trade or dive in and try to fix it myself, really don't have much to lose. Right now I am leaning towards doing the repair myself since all the parts would be like $350. But I am confused by a few things I am reading and hoping someone can clear it up so I feel a bit more confident.

1) Reading up on a timing belt FAQ the author says the water pump runs off the timing belt. But the sheave attached to it is for a V belt not a toothed belt. But to further confuse me, the water pump for my car does have a toothed sheave. I don't see a reference to the authors engine code but mine is an AWM. Can anyone confirm what the belt arrangement is on one of those? Unfortuantely I don't have the car local to check it out.
2) The gasket kits seem to include far more parts than I think I am going to use; like valve stem seals, cam seals etc. Should I really mess with these or just leave well enough alone? My feeling is if it isn't leaking and I don't break the seal why open another can a worms.
3) Same thing on the timing belt kit, it includes crank and cam seals...should I bother?
4) Plans are to buy the following at a min: head gasket, valve cover gasket, intake and exhaust gaskets, coolant flange, new head bolts, water pump, thermostat, belts, tensioner and tensioner roller. Are there any other parts you would recommend I do at the same time or at least check out? Any tips?

Thanks for the input.

Artiemas
08-02-2013, 06:13 AM
Honestly? Double check to make sure your HG is actually leaking. I was told both my bank, I have a 2.8, were leaking. I did my own test, triple checked it by another shop, and they said they were both fine.

It's rare to see these HGs go, but it is possible. Almost impossible unless you run no coolant on the .2.8

Believer
08-02-2013, 06:38 AM
I'll give a crack at it:

1. The AWM water pump is driven by the toothed timing belt. It is an internal pump, compared to the early style external. If you are looking at ECS they denote which engine which pump is for.

2. The cam seals are an easy replacement and with your mileage it may not be a bad idea to replace them. If you own a torque wrench, which you will need for this job, it is very easy to pop the bolts on the cams, slide the old seals off and slide the new ones on. The exhaust cam will be the only 'difficult' part because you will need to remove the timing sprocket on the end of it. If you have a wedge it is very simple to keep the sprocket in place while remove and reinstalling the bolt on the end. If you are popping the caps on the cams, you may want to also consider replacing the Cam Chain Tensioner gasket and half moon seal, common fail items.

3. I wouldn't touch the crank seal.

4. Your parts list looks good aside from the Cam Chain Tensioner seal and gasket.

Another system to keep in mind while removing everything is the PCV system. Over time the heat of the engine bay causesthese components (among many others) to become brittle. My brother had multiple PCV components basically deteriorate when removing during his engine removal, and his car was only at 115k. I also had brittle pieces fail on me when removing them for my head rebuild. During my build I lacked foresight on quite a few parts and if I knew then what I know now I would have just ordered the PCV parts preventatively. With an AWM you'd be focused on this (http://www.ecstuning.com/Audi-B5_A4-Quattro-1.8T/Engine/Emissions/PCV/ES279952/) part and this (http://www.ecstuning.com/Audi-B5_A4-Quattro-1.8T/Engine/Intake/Breather_Hoses/ES2515512/) which is currently not in stock, but can likely be found from other sources.

You will need this tool to remove and install the head, which can be found here: http://www.metalnerd.com/cat05.htm - Part MN3452 - Head Bolt Bit for 1.8T

http://www.metalnerd.com/images/products/cat05/mn18t160.jpg

I was anal about cleaning my block surface before reinstalling everything and used this 3m Roloc Bristle Disc - Yellow (http://www.ebay.com/itm/3M-ROLOC-BRISTLE-DISC-2-x-5-8-80X-GRADE-SINGLE-DISC-ONLY-7525-/230990388525?pt=LH_DefaultDomain_0&hash=item35c8199d2d) with one of these (http://www.ebay.com/itm/3-Roloc-Disc-Pad-Holder-Roll-on-Conditioning-Sanding-/160491145984?pt=Sanders_Sandblasters&hash=item255e048b00). I bought the drill attachment at Harbor Freight for like 4 dollars or something if you don't like ebay.

Pick up some of this at your local parts store to help remove all the gunk from the old headgasket, along with a plastic scraper.

http://images.motorcycle-superstore.com/ProductImages/OG/0000-Permatex-Gasket-Remover---.jpg

Hope this helps, good luck!

wclepse
08-02-2013, 06:41 AM
This is a 1.8...not sure if that make a difference in the likelyhood of a HG failure. But I do plan on checking it out a little more but I do remember seeing some coolant leaking on the front of the block when I did the upper and lower control arms like 3 weeks ago. Didn't pay much attention to it since I had minimal consumption at the time. Once I get the car back I will take a closer look but there is something leaking, could be the head or the water pump I suppose.

wclepse
08-02-2013, 06:51 AM
Believer...thanks for the input/confirmation. Figured the pump was on the timing belt due to toothed sheave but I guess I will have to dig in there to see how it is all laid out. Cam seals I will take a look at, just a little concerned about pulling the timing gear and messing up the timing somehow. The cam tensioner wasn't done too long ago so I am probably OK on that. I did read others mentiong the PCV system but wasn't sure which parts to focus on...thanks for the info. I know all of those lines tend to get brittle.

Is there a gasket sealer/prep anyone recommends?

Believer
08-02-2013, 06:53 AM
Believer...thanks for the input/confirmation. Figured the pump was on the timing belt due to toothed sheave but I guess I will have to dig in there to see how it is all laid out. Cam seals I will take a look at, just a little concerned about pulling the timing gear and messing up the timing somehow. The cam tensioner wasn't done too long ago so I am probably OK on that. I did read others mentiong the PCV system but wasn't sure which parts to focus on...thanks for the info. I know all of those lines tend to get brittle.

Is there a gasket sealer/prep anyone recommends?

I just slapped my HG on and torqued everything down, 3k miles laster everythings still fine.

As far the messing up the timing with the belt sprocket - as long as you keep the cams from moving while you detorque/retorque the bolt on the end, everything is gravy. I can provide some more info regarding this if you decide to take the plunge.

wclepse
08-02-2013, 07:14 AM
Same with the valve cover gasket? Pics of the gasket make it look a little flimsy so I thought a little sealant would help keep it in position. Can anyone confirm what size torx that is? Might be able to get one out of the shop here at work.

Believer
08-02-2013, 07:24 AM
Same with the valve cover gasket? Pics of the gasket make it look a little flimsy so I thought a little sealant would help keep it in position. Can anyone confirm what size torx that is? Might be able to get one out of the shop here at work.

For the valve cover gasket the Bentley calls to use a dab of sealant at two spots on the front of the engine, where the cam seal cap meets the head and at the back of the head where the Cam Chain Tensioner meets the head, basically the 4 spots where the gasket has to ramp up.

Which torx are you asking about, the ones for the Cam Caps?

wclepse
08-02-2013, 07:45 AM
Just realized it isn't torx...it is a polydrive for the head bolts. Doubt we have that here at work, especially in a 6" length. Just hate buying a tool I hope to NEVER use again. Maybe I will see if the local parts stores have them to rent/loan. But from what I am reading it is a 10mm polydrive.

Believer
08-02-2013, 07:56 AM
I feel ya on buying the one time use tools. I'm pretty sure my brother's head studs are triple square. If he is done with our Poly tool I could loan it to you.

wclepse
08-02-2013, 08:50 AM
Appreciate the offer...may take you up on that but I do have another question. You mentioned the cam tensioner gasket so I was checking that out here. (http://www.ecstuning.com/Audi-B5_A4-Quattro-1.8T/Engine/Gaskets_-and-_Seals/ES258759/) Thinking I should add this because they mention it can damage the coolant flange. I think the tensioner was done about 6 months before the flange started to show signs of leakage. Could be coincidence or could have been the start of the chain reaction. Either way it is cheap so I might as well do it.

walky_talky20
08-02-2013, 09:00 AM
I'm kind of doubtful your AWM needs a head gasket. What symptoms are there to back this up?

wclepse
08-02-2013, 10:02 AM
Well as I mentioned above there was coolant down the front of the block a few weeks ago when I did the control arms. But the rest of it is from the indy mechanic that said he put a scope under the cover and saw coolant stains above the water pump. Since he doesn't want to do a HG I figured he has no reason to lie and say it is leaking when it isn't. But I won't know for sure till I pull it apart. I do know the leak must be external only though as the coolant and oil were both OK. Other suggestion on what it could be? Can't think of any other source that high up that would end up on the block.

wclepse
08-04-2013, 03:18 PM
Started pulling it apart but got stuck on the bumper supports...need to pick up a T45...but looking through the fans it does look like the drivers side front corner may be looking.

Seerlah
08-04-2013, 03:28 PM
I am also skeptical about needing a new HG. So the mechanic said you have a bad HG and you are simply going to take his word as the absolute truth? Having "dried" coolant on the front of the engine by the water pump constitutes a failed HG?????

1) You didn't mention misfires
2) You didn't mention overheating
3) You did mention that you "did not" see oil mixed with coolant

Don't touch your HG. Replace your rear coolant flange and call it a day.

Edit: Noticed you said you saw a leak down the front of your engine. I am going to say your water pump is leaking (compromised seal). Look there.

wclepse
08-05-2013, 05:06 AM
Well again, if he said bad head gasket and wanted to bend me over on the repair I might be skeptical, but being that he only charge 40 bucks to pressure test and look the thing over I don't see why he would make up the leak at the head gasket. And I should have been more descriptive in my last post, it does appear like the head is leaking from the drivers front corner. Won't be able to tell until I get some more parts off to have a clear view of what is going on.

But to answer your questions, no misfires no oil mixing in either direction and only over heating happened when the flange completely died and I only let it get a tick or two above normal before I got to a safe place to pull off. But just because I don't have any of the above doesn't mean it isn't leaking, just means it isn't an internal leak. Which I am hoping is a good thing for the state of my head. I would think if I had all of the above I would be more likely to have a warped head.

wclepse
08-13-2013, 07:33 AM
Well I finally got a chance to really start taking things apart and man this is a bitch. 12 years of winter driving in the northeast has not been kind. It does appear as if the leak was the water pump shaft seal as you all expected. But I wasn't able to confirm this until everything was off, with the timing belt covers in place there was so much cast off in there you really couldn't see where the leak came from. My problem now is I can't get the two SHCS to budge on the water pump. Think I may need an impact wrench. I have been hitting them with penetrant but does anyone have any other suggestions? Hoping to get to mess with it more tonight.

Also going to do some searching on the coolant flange, but does anyone have any recommendations on the easiest way to get access to this? I know I did the temp sender with everything in place but that was tiny, not sure if there is enough room to sneak the flange in there.

walky_talky20
08-13-2013, 09:56 AM
SHCS on the water pump? It should be held in by three 10mm hex head bolts. They are somewhat special being metric M7x1.0 thread. They are pretty high quality fasteners. Never had a problem getting those ones out (as opposed to the crank pulley bolts, for example).

wclepse
08-13-2013, 01:26 PM
http://www.audizine.com/gallery/showphoto.php?photo=72543&title=20130812-194914-1&cat=500Yeah, there was one I think 10mm hex head bolt then the other two are SHCS. Just picked up an electric impact wrench from work to give that a go tonight. But here is a pic of what I have.
Wait just realized I can't attach pics directly...will have to try to upload to another site later. But definitely SHCS...think it was 5mm.

wclepse
08-13-2013, 03:40 PM
Wow. I must have been really tired lastnight. There was so much gunk on the bolt I didn't notice the hex on the outside. With a 10mm socket the pump was out in a minute. Not sure why they were also broached for a hex key but looking at the one I got off last night it too has the interhal hex, it is just filled with crap. So now I just need to get the tstat and coolant flange out and button her back up. Hoping to have more time this weekend.

walky_talky20
08-13-2013, 10:00 PM
Indeed, those special M7x1.0 bolts can also be engaged with a 5mm allen key. Perhaps for some sort of assembly line reason, or maybe just to offer another way to remove it. The allen option may be helpful in a tight area, for example.

wclepse
08-15-2013, 06:42 AM
Hoping to have the parts in by the weekend. Can anyone provide proper torque specs for the bolts? I can't imagine any are all that dritical but if I am doing it I might as well do it right.

wclepse
08-16-2013, 08:06 AM
Woot...just checked tracking. Parts should be delivered today. Hopefully I get time this weekend to get it all back together and hopefully there leaks will be gone.

wclepse
08-16-2013, 02:37 PM
Hoping someone can put my mind ar ease...got the parts and started to do belt only to find cam sprocket went ccw a tooth or two. I tried to get it lined upagain and install belt but i am off just a bit...no big deal I can always move it a little more but is it normal for it to spin a little?

wclepse
08-16-2013, 02:53 PM
So how much preload should I put on the tensioner pulley? The walkthrough I was following has a different set up

wclepse
08-17-2013, 12:39 PM
Have everything back together except upper radiator hose....stupid clip rusted and broke. Dealer only sells complete hose assy...seems silly for a cheap clip. Any other options to secure it? Found one place selling it for like a buck but they have a $15 min...at that point I might as well replace the hose at just over 20.

Seerlah
08-17-2013, 03:39 PM
You end up getting your timing lined up correctly? Make sure it is not off even one toothe before putting everything back together.

wclepse
08-17-2013, 04:42 PM
yeah...had to turn cam sprocket slightly cw and everything lined up. Got the tensioner done then turned crank till cam sprocket did one full turn and both marks lined up again so I think I am good. Checked with one dealer and they said clip is not available but the other said they can get it so I am hoping Tuesday night everything is done and leak free.

Seerlah
08-17-2013, 05:05 PM
After you are done with your timing belt kit, you are supposed to do at least 2 full rotations by hand on the crank bolt making sure that the lines match up on each rotation (markings on cam gear to valve cover and crank pulley to cover). I tend to do a couple more than that for good measure. If it is off, you can take the tensioner back out, place it in a c clamp, compress it, place pin back in, and reuse it (place back in when ready).

And the part number for that clip is 1J0121142. Call a VW dealership and ask specifically for this part number. They should be able to do it for you. If not, order online. The VW dealership I go to would take that off a radiator hose they have laying around just to help me out. There is a difference with customer service among dealerships. I go to this dealership for parts mainly for the customer service. Guy even gives me stuff for free sometimes. But I can tell he is an enthusiast.

http://www.ecstuning.com/Search/1j0121142/
http://jhmotorsports.com/shop/catalog/clip-retainer-for-radiator-hoses-p-1361.html
http://www.ebay.com/sch/i.html?_trksid=p3872.m570.l1313.TR0.TRC0&_nkw=1J0121142&_sacat=0&_from=R40

Just a few places you can get them if the dealership decides to sh*t on you.

wclepse
08-19-2013, 07:45 AM
Thanks...double checked this morning and they are ordering that part should have it tomorrow. I just wanted to make sure it wasn't the clip on the other side to the hard pipe. But thanks for the alternate places, the only place I found it had a min order.

cobaum
12-11-2013, 07:44 AM
Oh come on! I read through this whole thread to not hear how it turned out? That's like telling a joke without a punch line. Details! Pleaseeeeee!