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Tue Jan 17, 2017 10:04 pm

Long story short, I have had tuning issues since the 2054 was built in 2014. It has always been sensitive to tune and fouls plugs often on the 3/4 side. Recently I pulled the motor and decided to split the case to fix an oil leak, when I discovered that both of my DRD L5 heads are different. The 1/2 side spark plug thread seats flush how it should. The 3/4 side does not. Both plugs are close to 1/4" too short in the thread, which tells me that the head was not machined in that area enough. I have always used the correct long reach plugs as well (NGK D6EA).

What is the correct method to fix the holes on the 3/4 head? Machine the outer side 1/4" or the inside? Thanks guys

The first 2 pics are hard to see, but the bad head. The last is the good one for comparison.

Tue Jan 17, 2017 10:36 pm

I made a cutter to do it myself. Just HSS cutter welded to a shaft, and the shaft fits in a spark plug shell.

Time sert has a deal where you thread a TAP into the head, then use the shaft of the tap as the center, and it pilots a cutter.
https://www.belmetric.com/14x15-c-217_219_259/ts34156-m14x15-seat-recondition-cutter-p-7259.html
It is best to have it in a drill press or milling machine or VGS machine so you get a steady cut for sure.
Driving it freehand might get a little chatery or might not, I don't know, or might work fine.

Tue Jan 17, 2017 11:21 pm

Does that sparkplug not being long enough and being recessed like it is cause it to run rich like that. Looks like it's not even firing right to me? Like it's been missing a lot. So those are 3/4" plugs not 1/2"?

Wed Jan 18, 2017 7:19 am

Look at the barrel seating surface in the second photo. What it that spot on the left hand side?

Wed Jan 18, 2017 12:26 pm

I would remove material from the outside with a spot facing tool similar to what modok had mentioned. I wonder how many additional CCs you have with the plugs recessed like that? Or if it was taken into account when the engine was built?

Wed Jan 18, 2017 2:29 pm

Sigh. Another reason to stay away from that guy. SHEESH!
Yes, correct. You should remove material from the outside as Modok states.

T

Wed Jan 18, 2017 3:29 pm

I also had problems with my DRD heads. He cut too much off when fly cutting them. He then said I measured wrong because he doesnt make mistakes. I then asked how come all my numbers are still the same except where he cut? First and last set of heads I get from him. I like my Tims heads better. The mark is where the head studs are, cut through. Builder should have caught that when the heads were cc'd, spark plug.

Wed Jan 18, 2017 6:51 pm

Somewhere I read a thousand years ago that you were supposed to thread your plugs into the heads to see where the electrode ended up pointing.
The idea being you didn’t want the electrode to “hide” the spark, so you would index the electrode to face away from the closest cylinder wall.
Something like this:

So if a guy took the time to do that, he would see if he had a problem with plug protrusion or in this case lack of plug protrusion.
Just for grins watch the clear head engine running video:

Wed Jan 18, 2017 7:53 pm

Brian71 wrote: I wonder how many additional CCs you have with the plugs recessed like that?

About 0.85 ccs. :lol:

Wed Jan 18, 2017 10:23 pm

Ach60: I should have installed plugs before building yes, but most of us that spend close to $1k on a set of heads pay that, so that we don't have to deal with this type of garbage.

Jason is correct. There are actually more than one of these small holes inside the heads where they were flycut. This was the second set of DRD L5 heads I bought over the past 4 years. This set was cut for 94s. The first set was cut for 90.5 and did not have the extra holes where the metal was too thin. With the 94s, there are sections that look so bad, I would have done 90.5/92 should I have known.

Dan: Yes, I the NGK D6EA is the correct plug and 3/4" length. These are the only plugs I have ever run in all of these DRD heads. You are also right, 3/4 has always been difficult to tune and fouls plugs often. I pulled the carbs and plugs WEEKLY for months, until I got so fed up and decided to tear into the engine.

Honestly, I've been more pleased with heads from AA than these DRD heads. After 2 sets, I'm done. Just can't afford anything else yet.

Wed Jan 18, 2017 10:31 pm

Cb's new panchto castings have .200" thickness around the bore,SUPER THICK, actually may have enough meat to create bores larger than 94 :shock: And they feel HEAVY, unlike the china castings. Never bothered to weigh them but there is defenetely a difference.
Very excited about these heads!!!!

Wed Jan 18, 2017 10:56 pm

smitty24 wrote: Ach60: I should have installed plugs before building yes, but most of us that spend close to $1k on a set of heads pay that, so that we don't have to deal with this type of garbage.

I wasn't being insulting, Sorry if it felt that way.
I get bit by this shit working on Super Expensive Aerospace Hardware all the bleeding time.
But I don't think DRD machines in the heads for plugs, unless they buy just the casting which I doubt.
(I hate the fact that I'm defending these guys based on some of the reviews I've seen)
http://www.thesamba.com/vw/forum/viewtopic.php?t=219319&highlight=drd

Thu Jan 19, 2017 12:55 am

Just wondering what castings your L5s are based on. They have used several over the years (CB, AA, RM). The last versions Ive seen were the castings that did not pass QC for RM and were sold back door to EMPI with the RM logo ground off. Most I have seen were due to casting shift but since it was a QC issue that cased them to be rejected out of spec machining could also be the case.

Fri Jan 20, 2017 9:34 pm

These are the 049 castings. The first pair I had in 2011 were also.

That issue is being fixed. I split the case last night and have a couple other issues to resolve.

1. Rockers are CB Performance elephant foot, coupled to 1:25 rockers and bolt together shafts. #3 exhaust rocker tip separated from the ball the flat tip pivots on. It literally beat itself off the ball and has an extra .004-.006 of slop, in addition to the .006 freeplay the valve already has. (I use Aircooled.net's heavy duty aluminum pushrods.) I need to put a better quality rocker tip on these.

2. I discovered my #3 piston also ate something not on it's diet! I have no idea when this happened. Can I clean this up with a Dremel or does it just need to be replaced? The other 3 pistons are perfect.

I might disassemble the head and check the valves on that cylinder. Not sure if whatever was in there could cause valve damage or not.

Fri Jan 20, 2017 11:27 pm

Just a thought, 3/4 side always runs rich and #3 piston is damaged, any parts fall off that carb that may have found its way into that cylinder that could be causing it to run rich on that side?

I swear I am seeing bits of brass hammered into that piston in the third pic of the piston and some in the head near the exhaust valve and to the left of the spark plug on the head and on the actual intake valve in the first pic of the head you posted.

Like a jet or something fell out of the carb and was eaten by the piston.

Sat Jan 21, 2017 9:31 am

Keith, that is a possibility I have always wondered about. I never had this engine apart before, but it ran a bit different briefly after a club meet a while back. I was doing some experiments on this engine and was running open velocity stacks at the time. I am actually extremely careful when I do carb work around open stacks. I jam clean rags down them, use good lighting, keep my hardware/jetting organized and accounted for...that said, it doesn't mean accidents don't happen.

From the day I first fired this engine up, #3 has given me hell! The idle mix can be completely closed on that barrel and the engine won't stall. That side has always run rich and fouled plugs, no matter what timing or jetting ran. I never had this kind of trouble with an engine before. The original spark plug issue most likely didn't help, but this piston gouging is just salt in the wound. One of the rocker tips on that cylinder also beat itself out of the rotation ball (elephant feet from CB) and added extra lash.
I'm just hoping there isn't a bent valve or internal head damage, but I don't see why there would be. It doesn't make odd sounds or anything. I will dissemble that head regardless and check it out.

Sat Jan 21, 2017 12:44 pm

check to see if those swivel ball adjusters have 2 oil gallys in them. 1 going across the threads and 1 from that one to the ball. there were some that did not have the 2nd gally and as a result...you see what it does.... as far as the l5 heads...shit can them and get some good ones :shock: cb lostpanofcheetos. :wink: , .

Sun Jan 22, 2017 10:54 am

smitty24 wrote: Keith, that is a possibility I have always wondered about. I never had this engine apart before, but it ran a bit different briefly after a club meet a while back. I was doing some experiments on this engine and was running open velocity stacks at the time. I am actually extremely careful when I do carb work around open stacks. I jam clean rags down them, use good lighting, keep my hardware/jetting organized and accounted for...that said, it doesn't mean accidents don't happen.

From the day I first fired this engine up, #3 has given me hell! The idle mix can be completely closed on that barrel and the engine won't stall. That side has always run rich and fouled plugs, no matter what timing or jetting ran. I never had this kind of trouble with an engine before. The original spark plug issue most likely didn't help, but this piston gouging is just salt in the wound. One of the rocker tips on that cylinder also beat itself out of the rotation ball (elephant feet from CB) and added extra lash.
I'm just hoping there isn't a bent valve or internal head damage, but I don't see why there would be. It doesn't make odd sounds or anything. I will dissemble that head regardless and check it out.

I had the foot come off an elephants foot adjuster - It was because the adjuster was offset on the valve, so that it worked but the axis of the screw was too close to the edge of the valve stem. In the end, the rocker arm broke free (using stock wavy washers/clips which snapped) and slid sideways off the rocker shaft. Now I have solid rocker shafts, but stock adjusters, with it shimmed to line up properly with the valve stems.
Maybe the probem you have is that the rocker arms are not properly aligned with the valve stems, and the one that disintegrated was the worst.