Author Topic: Rebuilding AHU - any tips for power or longevity? (Read 11258 times)

MikkiJayne · « **on:** August 30, 2007, 04:26:45 am »

Hi everyone,

Well I'm about to undertake a total rebuild of my AHU after pulling the crank to fix the pulley wobble and discovering the bearings were worn out.

So the plan at the moment is to fit .216 nozzles (from dieselvw.com), ARP studs, and standard rings.

I'm wondering if there is anything else I could / should do while it's in bits? I'm aiming for 180-200bhp and 300-350lb/ft long term.

Oh, and should I do anything to the injection pump at 146K miles? It was running fine before, and isn't leaking so I'm inclined to leave that well alone :wink:

Any suggestions welcome

Mikki x

jtanguay · « **Reply #1 on:** August 30, 2007, 01:02:34 pm »

get some total seal rings. i've installed them on my tdi block. hillfolk'r and andy2 have them and they report NO blowby!!! very good if you want to run high boost levels to reach your HP goal.

of course std rings will last you a year or so before the ring gap increases enough to give you significant blowby, but why settle for that when you can go near zero blowby for a full 100-200'000km?

a bit pricey after the whole UPS customs ordeal, but i'm sure it will pay off in the long run.

MikkiJayne · « **Reply #2 on:** August 30, 2007, 01:15:21 pm »

Mmm I was contemplating them, but have had mixed reports from other users of them, particularly relating to them being difficult to bed in.

My block will be professionally honed, and will be going in a daily driver so I need something that will settle very quickly. Is there any special requirement for honing for these rings?

Cost is an issue too - they aren't cheap over here!

Thanks,

Mikki x

jtanguay · « **Reply #3 on:** August 31, 2007, 01:33:36 pm »

Quote from: "MikkiJayne"

Mmm I was contemplating them, but have had mixed reports from other users of them, particularly relating to them being difficult to bed in.

My block will be professionally honed, and will be going in a daily driver so I need something that will settle very quickly. Is there any special requirement for honing for these rings?

Cost is an issue too - they aren't cheap over here!

Thanks,

Mikki x

pretty sure honing procedure is the same. but you should buy their quickseat dry lube. makes the cyl walls turn green... helps the rings seat fairly quickly.

MikkiJayne · « **Reply #4 on:** September 03, 2007, 09:16:36 am »

No other suggestions?

jtanguay · « **Reply #5 on:** September 03, 2007, 12:29:02 pm »

so you're saying you had the crank wobble on an AHU? that seems very odd... the alternator should be one way, to reduce the shock load on the crank. check and make sure that your alternator has the one way pulley.
if it doesn't, then put that on your buy list.

MikkiJayne · « **Reply #6 on:** September 03, 2007, 02:01:52 pm »

The engine didn't come with an alternator so I have no idea what it had originally. A one way pulley is on my shopping list tho.

MikkiJayne · « **Reply #7 on:** September 11, 2007, 03:25:14 pm »

Back up again...

Does anyone have any recommendations on where to get ARP studs and Total Seal rings in the US please? They're too damn expensive here so I'll buy 'em in the US and have a friend ship 'em over :wink:

Thanks!

Slave2School · « **Reply #8 on:** September 11, 2007, 03:53:43 pm »

summit racing sells studs as well (ford cosworth kit is installed in my car).

MikkiJayne · « **Reply #9 on:** September 11, 2007, 04:36:59 pm »

Got 'em thanks

Less in $ than in £! We get ripped off for everything :mad:

hillfolk'r · « **Reply #10 on:** September 11, 2007, 05:28:21 pm »

Quote from: "MikkiJayne"

No other suggestions?

yea....when i got my "total seal" rings,they werent made by total seal

they had me buy oem(goetze) rings and send them to total seal to be modified into gapless(they were impressed by the oem quality,and figured why mess with a good thing)

it cost about 20$ a hole to mod the rings,and yea use their dry film lube on the cyls(cost shipped was 125$ to mod the rings,and extra goodies,this is on top of the cost of the oem rings)

when you fire it up,let it idle long enough to get oil psi,then hold the revs at 1500-2000 rpms,every once in a while blipping the throttle hard up to 3000 to load+seat the rings
let it run about 15 mins like this,then get it out+drive it

dont sit there running it more than needed,without loading it by driving
my bores measured out good,i used a "dingleberry" hone (approx 280-320grit) and got a nice crosshatch
try practicing on an old block if you can
i found that my 18v dewalt on low,and moving up+down 1 complete stroke a second gave me a nice crosshatch
im also running kermas race 520s

MikkiJayne · « **Reply #11 on:** September 12, 2007, 03:30:10 am »

Interesting...

I found the rings listed on their website part number S9205 (can't link to it but you can search on the part number), and also found that number on Summit as TSR-S9205 for $117. There's nothing saying they need a donor ring to make them :?

I'm planning on buying the full set from Techtonics. I don't know what make they are but I assume they'll be pretty good from them. I was just expecting to throw the 2nd ring away if I get the Total Seals as well...

I'm getting the block profesionally honed by an engine shop, although from your description their tool sounds like the same thing you used.

Edit: I just spoke to Total Seal's main distributor in the UK and in fact they supply a full set of rings with gapless 2nd, rather than just the 2nd as I was expecting. It is also common for them to modify existing rings when the rings are already supplied with new pistons which makes sense.
Price for a full set is only £70 ($140) which is much more reasonable than I expected, and only £30 ($60) more than the standard ring set I was going to get from TT.
Very pleased

Mikki x

Bojje · « **Reply #12 on:** November 06, 2007, 04:47:12 am »

I've heard that the ARP studs should be avoided on TDI's because the head lifts according to people on tdiclub.com

Stock studs work great. One dude's running stock studs and 258 bhp without any problems.

jtanguay · « **Reply #13 on:** November 06, 2007, 01:12:35 pm »

Quote from: "Bojje"

I've heard that the ARP studs should be avoided on TDI's because the head lifts according to people on tdiclub.com

Stock studs work great. One dude's running stock studs and 258 bhp without any problems.

well if the heads lift, wouldn't that give a good hg leak?

Bojje · « **Reply #14 on:** November 06, 2007, 01:19:09 pm »

Quote from: "jtanguay"

Quote from: "Bojje"
I've heard that the ARP studs should be avoided on TDI's because the head lifts according to people on tdiclub.com

Stock studs work great. One dude's running stock studs and 258 bhp without any problems.

well if the heads lift, wouldn't that give a good hg leak?

Well that's why he should avoid them...

I have no personal experince of the studs on TDI engines, but that's what I've read on tdiclub.com. The stock ones seem to work well to so there's no idea changing them.