Engine rebuilders: "Input Required"

Engine rebuilders: "Input Requested"

Here is a series of photos of a NB TDI engine. There are four (4) cam- followers that are trashed but no sign of impact between the pistons or the valves!
Befor I put this engine back togeather should I replace the valves?


Photo of the cylinder head removed for inspection:

Note: A close-up of #1 & #2 valves After cleaning , no indication of pistons impacting the valves.



A close-up of #3 & #4 valves:


A shot of #1 & #2 pistons:


A shot of #3 & #4 pistons:

Herm, how many miles? I would think that if they were trashed, there had to be some kind of binding on the valve stems.

Even if the valves are good, I would want new guides and seals in there. If valves are perfect, should be a minimal cost at the machine shop.

paramedick said:

Herm, how many miles? I would think that if they were trashed, there had to be some kind of binding on the valve stems.

Even if the valves are good, I would want new guides and seals in there. If valves are perfect, should be a minimal cost at the machine shop.

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There are 127K miles on this engine. The valve guides and seals are a piece of cake to replace. I am just stumped as to how this happened?

If the lifters are trashed, were they in pieces? If they were worn a lot, but never completely failed, might that explain why the valves didn't drop into the cylinders?

Herm, I looked at your pictures and saw the same thing I saw in the Beetle engine I have in my garage. Take a close look at the areas I circled.



In my engine, there was just a small area where there was a tiny bit of displaced metal in the same place I see marks in yours. Maybe what I see in yours is just the way it was cleaned though.

whitedog said:

Herm, I looked at your pictures and saw the same thing I saw in the Beetle engine I have in my garage. Take a close look at the areas I circled.

(Photo cut to conserve loading time.)

In my engine, there was just a small area where there was a tiny bit of displaced metal in the same place I see marks in yours. Maybe what I see in yours is just the way it was cleaned though.

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I just double checked all of the pistons. Found no indents or other signs of damage.
But thanks for your observations and sharing your experieance.

I did some more cleaning and things are looking good.
I'll have further information this afternoon and make a determination as to what parts will be replaced.

OK...I now have an idea as to where I'll be headed with this "project".
After talking to an "Ol'e Hand" at cylinder head buuild/rebuilding the machinst showed me how to check for "blow-by" at the valves with the cylinder head removed.
Amazingly simple procedure.
1. Ensure the surface of the head/valves are CLEAN
2. Apply a liberal amount of light oil (WD-40) to both valves (Cylinder #1) onto the face of the cylinder head.
3. Using compressed air and a blow-gun blast air into a valve port (intake) and observe the face of the valve. If you see bubbles or puddling at the joint between the valve and the curface of the cylinder head you have a prime indication of blow-by.
4. Repete this procedure for the other seven (7) valves.

I did this and found #4 intake valve leaking. This is an indicator that either a valve stem is bent or the rear face of the valve is not seated flush onto the valve-seat (distorted valve head).

What I will be replacing are all 8 valves and the seals and a set of cam-followers. I ordered a set of valve guides but I doubt those will be needed. Due to the fact that there is no visable sign of impact and the minimal damage.

The only thing I'll need to do is lap the new valves into the valve seats.

I think you are much better off replacing all rather than none. Minimally, I would replace all the ones that had damage on the lifter. Any impact can compromise the integrity of the valve. There have been too many cases where people did a visual check, thought they were ok and XK miles later the valve head fell off and ruined the piston and bore.
Better to spend and extra 150-200 now than have an unwelcome surprise later.

Herm
While you have all the parts you just as well replace the guides. Then you know it will be good for sometime. Another way to check the valves is use a dial indiactor and check for run out. But this means pulling the head apart. I'm sure you know this but make sure you lap the valves intot he seats.

Greg

stuff to do

Since you have it apart treat the cylinder head to a valve job so that when you lap the valves you are doing it to a known good surface as well.

And go ahead and put in the valve guides. With 120K+ they have got to be worn and since that is what keeps valves positioned ( you did do the "wiggle" test on the valves ? ) won't hurt to replace while it is easy to do. And let a shop do it as well.

Rob

Could the trashed cam and lifters be from wear through? I remember people here saying that you better check your lifters. I guess there were some that showed signs of wearing all the way through and then breaking.
Just a thought.

rjr311 said:

Since you have it apart treat the cylinder head to a valve job so that when you lap the valves you are doing it to a known good surface as well.

And go ahead and put in the valve guides. With 120K+ they have got to be worn and since that is what keeps valves positioned ( you did do the "wiggle" test on the valves ? ) won't hurt to replace while it is easy to do. And let a shop do it as well.

Rob

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Hi Rob,
Though this would be ideal (compleat valve job) the costs would be more than the price of buying a new cylinder head.

I can remove and replace the valve guides (thats the easy part). To have a machinist ream the new guides to tolerance and replace the valve seats. The new seats would also need to be machined. These two procedures are very expensive compaired to the cost of a head replacement.

New valves and seals and cam followers for now untill I inspect the new valves for any excessive run-out. At that point I'll look at guide replacement.

cage said:

Could the trashed cam and lifters be from wear through? I remember people here saying that you better check your lifters. I guess there were some that showed signs of wearing all the way through and then breaking.
Just a thought.

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Cage...this is a good point especially when the prior owner has been using the wrong type oil

On the road again~

Well.....today this NB engine is running once again!

Compression is good...timing is dead on.

Now all thats left is all of the small stuff ...plenum assembly, hoses , air-intake plumbing ect...ect.

Another success from wits end!!

Super Herm. Again you demonstrate that perseverance pays off.

The owner better be appreciative. You did a lot of work to a poorly maintained car. With care it should run well for the next 350k+ miles.

Great Job Herm

PeterV said:

Super Herm. Again you demonstrate that perseverance pays off.

The owner better be appreciative. You did a lot of work to a poorly maintained car. With care it should run well for the next 350k+ miles.

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peter, that is my car, the beetle that had all the problems at the HO5G gtg, and yes i do appreciate all of the work herm did to my car. he is a great mechanic! whoever owned that car before me treated it like crap but i do take responsibility to some of the problems by running the wrong brand oil in it. as soon as i get it back i am going to get the right oil for it. one more thing, how often should i be changing the oil? i hear lots of different mileages.

Thanks, Donny

TDI-kid410 said:

...Snip...Snip... how often should i be changing the oil? i hear lots of different mileages.

Thanks, Donny

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Simple answer:
Using the correct type and grade of oil: 5-W40 CI-4 synthetic use the offical VWoA recommended interval of 10,000 miles.

Oil filters are another issue. Stay away from Fram, NAPA, ect..ect.
Having said that, Mann, Bosch, Mahle, and other high quality filters use superier filtering media.

So it all boils down to a simple answer for long term relaibility and lower maintenace cost use quality oil and filters. The same applies to the engine air filter and the cabin filter.

As far as the brand of oil...there are several to choose from. The thing to remember is the oil specification:
5-W40 CI-4 Synthetic. If the oil does not meet this specification do not use it in any ALH, AHU or 1Z engine.

Herm TDI said:

Oil filters are another issue. Stay away from Fram, NAPA, ect..ect.
Having said that, Mann, Bosch, Mahle, and other high quality filters use superier filtering media.

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NAPA Gold filters (made by Wix) are no good? Hmm... I guess I should stop buying them ten-at-a-time....

I'll have to disagree with you on this one, Herm. I changed the oil in a friend's TDI a couple weeks ago. He had MANN filters, I had an extra Wix filter with me, we compared them side-by-side. Both were/are excellent. Excellent design, materials, and construction.

TornadoRed said:

NAPA Gold filters (made by Wix) are no good? Hmm... I guess I should stop buying them ten-at-a-time....

I'll have to disagree with you on this one, Herm. I changed the oil in a friend's TDI a couple weeks ago. He had MANN filters, I had an extra Wix filter with me, we compared them side-by-side. Both were/are excellent. Excellent design, materials, and construction.

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that is correct when specifying napa GOLD filters, (made by wix) but napa carries more than one grade of filters, so one must be careful. Wix is as good as any that are considered "best in class". I have a lengthy history using wix filters... I have always used them on my personal and business vehicles, and have not experienced component failure, due to poor filtration.
the hands on method to compare filters ,is to cut just the ends off (NEW) media, unroll/spread out and look at sq/in size of material, then hold up to a bright lite, and look at density of media (Microns), less light means more filtration.
I have been using mann filters with the alh/tdi after doing this comparison myself for two reasons: 1- very good media... no compromise when compared to wix, 2- great price break from tdiparts (watch the specials, buy in bulk)when compared to my local napa dealer.

this is a good method to check for engine wear at oil service intervals, small particles will be collected here

boostin said:

Wix is as good as any that are considered "best in class". I have a lengthy history using wix filters...

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I can get the Wix #57210 (aka NAPA Gold) here www.fleetfilter.com/oilfilters.html for just over $4. That compares to about $8-9 at NAPA dealers.

I bought from another online source before I learned about this one, and still have five or six left. So it will be approx one year before I need to order again, unless I share from my stock.

Thanks.. i have a case on the way