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Discussion Starter · #1 ·
I've just purchased some parts for my AUM as Im going forged rods and an overall engine overhaul and Im curious whether everyone who rebuilt their motor had to rehone their block? I've seen a few build threads where the original honing marks are still visible and left it and just put their new internals in so Im assuming their piston rings bedded in without any problems but I'm not sure what mileage their engines were, as mine is coming on 122k

Also what running in procedures did everyone follow? Did they break it in gently for the first 500 miles keeping under 3000 rpm, changed oil and filter and increased revvs slightly thereafter? Im running ~240bhp and figured it's low enough for the running in as long as I take it easy. Anyone else use any other variation of this process?

Thanks
 

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Discussion Starter · #3 ·
I really want to change my piston rings while im there, the mileage on the engine was quite high when sold to me and there's quite a bit of blow-by gase so would be worthwhile changing them when i give the engine a once over. I might just remove a spark plug and stick one of them fibre optic cameras inside to have a look before i buy.

By the way thanks chris for replying
 

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Discussion Starter · #4 ·
No one feel like discussing their break in procedures?

I'm still undecided as to how I plan to run in the engine, but I might try run it in on a dyno get with some progressive hard runs when the oil is up to temp to get the rings to bed instead of the gentle run in.
 

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take a look when it comes out, make sure the bores arent all shiny, sometimes you can just give em a bit of a rub down and whack new rings in

Beauty of these engines is they arent knife edge cry baby fall apart at the drop of a hat like subarus or similar.

rare to hear of a bottom end going on a 1.8T for anything other than a big turbo with no internal upgrades.
 

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as for running in just change the oil as often as you can be arsed (id do 500 miles or so) and keep it under 3.5K revs until about 1500 miles or so then just service it as normal.

again, those engines are not made from chocolate.
 

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pauly4226
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have done a few engine builds, have always honed the bores,always big ends with the rings,and with an engine running some boost id personally use arp big end bolts, just dots the i,s and t,s.got a bit anal when doing a refurb, discard core plugs,paint block then renew core plugs.every engine builder will tell you different, me,i run relativly easy for the 1st 500 miles or so,keep below 3000 and dont be shy running in 4th @1200/1500 rpm,just loads it up and beds in sweet,change oil and filter,break in for another 1500, much the same ,change oil again, then give it beans! but thats just me is all, hope its of some help
 

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Discussion Starter · #10 ·
I'm just going for a light overhaul, I've bought ARP head bolts and ARP rod bolts, IE forged rods with calico coated big ends, new valve stem seals too while I've got the head off, apart from that Im also changing piston rings, oil pump timing belt, tensioners and water pump again

That mototune link suggests running it in very differently from convensional methods:

3 x 30% throttle to 30% rev range

3 x 50% throttle to 50% rev range

3 x 100% throttle to 100% rev range

all in the first 20 miles of the new rings life.

What mototune recommends makes sense I'm worried if I take it easy I might not get an optimum seal, I see no reason why there would be any problems with the hard run in if all fluids are up to temperature and oil and filter is changed immediately after the first 15-20 miles of the engine's life.
 
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