exvaux

iTrader: (1)

because people have used regrinds then need another bottom end very quickly.2 reasons not to regrind subaru cranks different to evo/gt4 etc is that 1 the hardened coating on the crank is very thin,grinding makes it thinner or non existand in places=bad and 2 its nigh on impossible to completely clear the oilways on the crank,even the slightest little bit of swarf will destroy your new bearings and reground crank in a few miles.if ZEN,API and RCM say dont do it then i'd tend to listen to them,just my 2 cents worth

W1ndowLicker

Like Ive said before Im not trying to argue with people or prove anyone worng so please dont take any of my posts the wrong way but the flipside of your comment is that if I had only phoned scoobyclinic (which as far as Im aware are well respected on here) then I would presume it was OK to do.

Also people are saying theres no way to clean them out but looking at it I cant see why not, they appear to be the same as any other crank. Using a high pressure line and brake cleaning fluid then I cant see why any pieces that might be in the oilways wont be blown out. The only place they can collect and may pose a possibility of getting stuck is in the ball bearing cavity at the end of the oilway but the sheer pressure and vacuum effect should mean that wont happen.

The hardened crank lining (as far as I can tell) is on the V9 cranks onwards, mine apparently doesnt have that coating.

Does anyone have personal experience of using a grind and it either working or failing ? or just horror stories ?

W1ndowLicker

Anyone at all ever used a re-grind ?

W1ndowLicker

Bump - Anyone ? - Bump !

merlin24

iTrader: (1)

Never fitted a reground crank into an EJ20/22/205/207/257(delete as applicable) but have seen enough failed ones with reground cranks in them and no other signs of why it has failed eg Incorrect Assembly,lack of engineering hygiene,oil starvation,det damage,over fueling/mapping problem,MAF failure,coolant problems etc etc.
Obviously you dont want to spend more money than necc on the build, but with the worst case scenario - can you really afford to do a full strip and build on it replacing the crank,big ends,mains etc.
You may be lucky and the engine will be fine but i can guarantee you that it will always be at the back of your mind when its back on the road.
Your call at the end of the day TBH.

Mick

Phildodd06

I was going through this

I currenty have the V9 crank & ACL bearings, i work with an old skool engine builder, who has pleanty of experience in this department, he told me i could regrind, untill i metioned it was Nitrided to which he replyed if its nitrided, thn proberly best to replace
But if yours is not nitrided, then theres no real reason not to have it reground

Most pls will advise not to regrind, because if for what ever reason it fails again, they wont want you ringing up saying ' you told me i could regrind blah blah blah'
Its just to cover there own backs, and im sure you will agree, if they are building you an engine, its easyer for them to fit a new crank to your engine than have the hastle of taking your crank down to be ground and collecting it again, also more money for them.
(Not having a go, or accusing any engine builders, but as i work in the trade i know how it works (the more money the customer spends, the ore money our company earns))

Eprom

I would be asking 4 thou off a Subaru crank, there goes the Hardening process, wouldn’t risk it for the price of a new v9 crank. IMHO

W1ndowLicker

Thanks for the replies guys, Phill Dodd seems to have the same thoughts as me about this and im glad to hear someone else's opinion that matches mine.

Eprom, as far as I can tell my V4 crank isnt hardened/nitrided so that shouldnt be an issue compared to the V9 unless anyone can tell me different ?

Put the crank, bearings etc in and sealed the blocks last night, everything seems OK so far but obviously it would at this point ! Cleaned out the crank with a 150psi air line and **** loads of brake cleaner so cant see why it should have anything left in the journals.

Either way this turns out I hope theres no big 'I told you so's' from either side !

merlin24

iTrader: (1)

Hopefully you have managed to clean the oil drillings out 100% on the crank and the oil clearances on the big ends and mains are within spec.
Good luck with the rest of the build and make sure you clean out the main oil gallerys (remove the oil restrictor on each head and clean the gallerys and then refit the restrictors)on the heads if your bottom end failed.

Mick

Phildodd06

Normal cranks are reground all the time
Why would it b an issue on a V4 crank if it is not hardened in anyway?

W1ndowLicker

I just thought Id put a bit of an update in on this one.

Its all back together and fired up yesterday with no nasty rattles at this time, phew so far.

Some minor blow from the turbo/downpipe and a couple of small amounts of water and oil around that could either be small leaks or weeps but could just be from in the chassis or on the engine from the build and re-fit.

Driven it home from my m8s house who done the build which is about 10 miles and it drove as I remember it, nothing rattling or banging and temps looking good.

All my gauges are going in soon so I can keep a better eye on things as I run it in.

Ill keep you posted with how it turns out.

W1ndowLicker

Forgot to answer the question about the actual title thread !

I did replace the modine in the end, and the sump as the baffles just wouldnt allow it to be cleaned properly, and I found a place online that sells the sumps for £40 which I thought was a bargain !

Have gone with the ground crank as I said I would and only time will tell if it was the right thing to do.

silent running

Well, good on ya, is what I say. If you're willing to take a chance on it and see if it works, that's good data for the rest of us when it comes to rebuild time. I am going with a new modine and a second hand crank that measures up within spec. It had a couple of nicks but I took those out with an oilstone and it seems to be OK in the block. Cleaned out the sump with a load of carb cleaner and a hose and it seems OK so that's being reused as well. Keep us posted on how the run-in goes.

I can totally agree with what Phil says re: replace rather than fix a crank. If I was running my own business rebuilding engines, I'd always replace a crank instead of regrind, after all, I wouldn't want to take the heat if 3 months down the line my customer comes back with a knackered engine -and of course I wouldn't personally have to pay for the new crank anyway. It's a no-brainer. However as a private individual looking to save money the regrind option has to be looked at seriously.

I mean, the crank's running on a film of oil so I don't see why it needs hardening at all? OK it might be nice to have something super tough all the way through, but what good is a thin layer of surface hardening to something that shouldn't have anything touching its surface anyway? It's not like say a valve stem tip which is taking a serious pumelling the whole time.

W1ndowLicker

Thanks for the encouragement, it makes a change to hearing the doomsayers

On the sump side of things if yours is a baffled one aswell then I'd definately recommend getting a new one as they are just too damn hard to fully clean out IMO. Heres the link where I got my one from -

BEEVERS Auto Panels and Automotive Products

code 80-15-726 is for the turbo one, which is cheaper for some reason ??, supply and demand I guess.

As you can tell Im not one to splash out money just for the sake of it but considering the amount of metal in my sump and considering the cheapness of a new one I thought it was worth adding to the cost of the build

W1ndowLicker

I also got one of those magnetic sump plugs on flea bay for cheap ££, Ive always thought they were a gimmick but for the cost I thought its gotta be worth a go just in case, every little helps and all that !

The magnet is surprisingly strong aswell, had a hard time screwing it in cos it kept trying to stick to the sides of the thread ! lol

silent running

Bloody hell I never realised they were so cheap. I would have had one of those sumps if I'd known! I actually had a second hand one that I picked up for buttons and it only had a little bit of gritty sludge in it, so not too much of a problem. I did get one of those mag sump plugs as well though LOL. It was either get that off ebay for £6 or buy a new sump plug cos mine was rounded off. A no-brainer really. Can't do any harm.

W1ndowLicker

OK, a little update.

The engines back in and is in the process of being run in. About 250 miles on it so far and theres no nasty knocking yet ! (fingers crossed)

Only real problem is the clutch unfortunatly got some oil spilt on it during the build and as such is now slipping when giving more than half throttle so needs another clutch but thats not the end of the world.

So as I say, fingers crossed for the future but so far so good !

silent running

Glad to hear it. Keep up the good work! I did get a replacement modine myself in the end, very very cheap from Import Car Parts via ebay originally.

W1ndowLicker

After looking at the modine and the amount of metal in the sump, replacing it when doing a rebuild I think is something you definately have to do !

Forgot to mention when doing the 150 mile oil change the sump magnet didnt have any big bits of metal on it, just a slightly small amount of metal pasty stuff on it, it seems to just be minute bits of metal that were left inside mixed with the oil, nothing to worry about.

silent running

Cool, well we will see what happens once mine's up and running. I'll be doing the first oil change after twenty minutes of running it gently up and down the road! Then another change at 100 miles, then another at say 500. I've got some cracking cheapo oil to put in, I thought I was doing well to get the Tesco 10w40 mineral for a tenner but then Asda had some that was even cheaper, and now I've found the ultimate running in stuff - Morrisons own 10w40 which is something like £6 for 5 litres!

nampahc01

well i have bought i 97 wrx import which has just blown up!!! looking bak the paperwork it had a re ground crank 3 years ago in a re build!!!!

well u want a reason not to do it i'll give u one, where is the weak point in a big end bearing? the shell bearing its self. so you grind the crank you have 2 put in oversize bearings hence making the weak spot even bigger. any play start well it destroys itself very quick. also cranks are built that size for a reason with that amount of hardener for a reason. so you grind them it just makes the crank weaker and the bearing weaker.

so basically buy a new crank!!!!! and a new modine cooler and sump. im in the process of rebuild and the place im dealing with have told me everything 2 replace to do it properly.

im going 2.5 though just for some more power and ft/lbs

silent running

Well fair enough, but then I could equally say, mine had a rebuild with a 'not-reground' crank a couple of years ago, and that failed.

nampahc01

i've used a re ground crank and it doesn't work, lasted 3 years and went knock knock again. for a long lastin repair do it write and buy proper bits. phone a specialist and take there advice they know wat there talking about!!!!!! i've dealt with roger clark they seem very good.

nampahc01

as regrind doesn't work, i had a re ground crank in my wrx and it went knock knock not long after. cranks are built the way they are to make them as strong as possible you grind the hardener away and you just weaken them! plus means you have 2 put bigger shell bearings in which is the weakest part of a bottom end, so there for making the already weakened big end even weaker!!!!!!!!! so it will run a big end in no time.

mine had the uprated oil pump all the bits u need and it still run the big end.

buy a brand new short engine or just buy better internals. and spend some money to make it rite. basically you have the engine out so that is ur chance to make it rite. 40 quid for a re grind is very cheap!!!!! they have 2 do a very good job of a re grind for it to even work. i got quoted 200 quid

maybe re grind a crank on a corsa or saxo but not a impreza!!!!!

phone tim at roger clark they seem to no what they are speaking about. i dealt with him and he managed to sell me the forged 2.5 short engine. coming tomorrow so my toy will now be a bigger toy.

nampahc01

the chances are yours was re built with a new crank and and oil style oil pump. hence it went again.

W1ndowLicker

Sorry mate, but many of the points you've made there seem to indicate you may not have actually properly read any of the previous posts and are just another scaremonger who does everything by the book that the engine builders wrote !

W1ndowLicker

Either that or you work for Roger Clark !