Question for the machinists in here
+ Reply to Thread
Results 1 to 6 of 6

Thread:
Question for the machinists in here

  1. #1
    Senior Member lbhsbz's Avatar
    Join Date
    Oct 2008
    Location
    Long Beach
    Posts
    1,617

    Default Question for the machinists in here

    Now that the boat is sorted out (for now) I decided to tear into the 22RE turbo engine in my 4x4 that I rebuilt 2 years ago (less than 7K miles) that has been burning oil since day one.

    I ran it pretty hard on the way to the trail our last time out...turbo got a bit hot and cooked the shitty aftermarket manifold/turbo gaskets..in removing the turbo I noticed that the intake pipe from the airbox (which has a crank vent hose going to it) was full of oil...upstream of the turbo...so off comes the head. There were no hone marks left in the cylinders. I pulled the pan tonight and yanked the pistons out. There is a bunch of carbon (or coked oil) between the top and second ring on the pistons, indicating that the top ring wasn't doing a whole hell of a lot. These rings were from "safety gaskets" along with the rest of the kit...pistons, bearings, and everything else. The ring kit is cataloged as chrome rings.

    My question. WTF would cause this to happen? My machinist says he uses 280 grit stones for cylinder finishing on chrome ring application and has no reason to beleive that any other stones were used on mine. I broke it in on 5W-30 valvoline conventional oil....which is the correct oil for this engine, and it's been changed 4 times since the build (every 1500 or so miles).

    Here's the dimensions that I know were 100% dead nuts in specification...near the middle of the spec:

    Piston - cylinder wall clearance
    ring gaps
    ring groove clearance
    crank endplay
    main and rod bearing clearance

    My notes from the build are on a piece of paper in my FSM over at my Dad's house...I'm picking it up in the morning so I can put some numbers up here.

    Plan of action was to wrap the crank with rags, re-hone in the truck and assemble with new OE toyota rings, but I'm also seeing a small ridge at the tops of the cylinders and the bearings are showing signs of oil starvation (this is one I've gotta figure out as well...oil pressure has always been good), so the motor is coming back out and more money will be thrown at it...but I'd like to figure out why it failed before I put it back together.

    I'll try to get some pictures up in the morning.
    Last edited by lbhsbz; 08-28-2009 at 09:37 PM.

  2. Remove Advertisements
    PerformanceBoats.com
    Advertisements
     

  3. #2
    steelcomp was here
    Join Date
    Dec 2007
    Location
    n/e TN
    Posts
    26,271

    Default

    If there's a ridge, you've just flat worn it out. Might not be the best of block material for a boosted app. I'm not a huge chrome ring fan, even in boosted apps...and this is the reason and result. They don't break in very easily and are hard as shit on cylinders.
    If God is your co-pilot, change seats!
    Acts 2:38, the perfect answer to the perfect question.

  4. #3
    Senior Member lbhsbz's Avatar
    Join Date
    Oct 2008
    Location
    Long Beach
    Posts
    1,617

    Default

    Quote Originally Posted by steelcomp View Post
    If there's a ridge, you've just flat worn it out. Might not be the best of block material for a boosted app.

    Its a factory turbo deal...toyota built it that way. Turbo is stock (and new) Went 180K miles before some dipshit threw a non-turbo oil pump on it (different pressure passages than the turbo pump) and wiped out all the bearings. I bougth it, went through the motor...no expenses spared, and it lasts for 7K miles.

    The OEM rings from toyota that I just ordered (and now have to send back, pending cylinder measurements as soon as I get my book from Pop's house) are also chrome rings...

    How come it worked for toyota but not for me, even when I adhered to their specs?

  5. Remove Advertisements
    PerformanceBoats.com
    Advertisements
     

  6. #4
    steelcomp was here
    Join Date
    Dec 2007
    Location
    n/e TN
    Posts
    26,271

    Default

    Quote Originally Posted by lbhsbz View Post
    Its a factory turbo deal...toyota built it that way. Turbo is stock (and new) Went 180K miles before some dipshit threw a non-turbo oil pump on it (different pressure passages than the turbo pump) and wiped out all the bearings. I bougth it, went through the motor...no expenses spared, and it lasts for 7K miles.
    That sucks. It gives you an idea of how "good" factory assembled engines are. It can be very hard to duplicate some times. I'd contact Toyota and find a good knowledgable tech, and get his input. Just the grit alone isn't all that's involved in cylinder finishing, I know that much. Chrome rings are a bitch.
    You've obviously got some taper in the cyl's now...probably going to need a bore.
    If God is your co-pilot, change seats!
    Acts 2:38, the perfect answer to the perfect question.

  7. #5
    Senior Member lbhsbz's Avatar
    Join Date
    Oct 2008
    Location
    Long Beach
    Posts
    1,617

    Default

    Quote Originally Posted by steelcomp View Post
    That sucks. It gives you an idea of how "good" factory assembled engines are. It can be very hard to duplicate some times. I'd contact Toyota and find a good knowledgable tech, and get his input. Just the grit alone isn't all that's involved in cylinder finishing, I know that much. Chrome rings are a bitch.
    You've obviously got some taper in the cyl's now...probably going to need a bore.

    LOL...I am that skilled tech...factory trained. I spent 5 years at toyota...probably built a few hundred engines (I was young...I liked heavy line work) and never had one do this. We always used factory parts though. Never had any problems with rings seating...even on engines where I just used the 3 stone "glaze breaker" hone with 200 grit stones. Its funny how customer engines are always fine, but I seem to put that extra level of effort into my own because time is not important...and I seem to have problems more often than not. I don't get it.

    I'll measure everything up in the morning and see where I sit...I'm in agreement with you that from the looks of things...rings and a quick hone won't cut it. After keeping the boat running all summer...I don't have the money for this shit right now.

  8. #6
    Platinum Member BigSteve's Avatar
    Join Date
    Feb 2008
    Location
    Close to the water...
    Posts
    2,014

    Default

    I work on big diesel engines that use chrome rings most of the time. always use OEM kits or parts.The big engines use a wet sleeve assy, factory honed true. we test the engine blow-by with a road draft tube restrictor and measure it in inches of water column. Dirt is the enemy,doubble check air intake seals. on big truck and heavy ag equpt the air filer seal is so inportant it is recommened to replace the filter if the sealed unit is tampered with ie opened insteed they use a manifold restriction gauge
    If you ain't the lead dog the view is always the same !

+ Reply to Thread

Quick Reply Quick Reply

Register Now

Please enter the name by which you would like to log-in and be known on this site.

Please enter a password for your user account. Note that passwords are case-sensitive.

Please enter a valid email address for yourself.

Please select your insurance company (Optional)

Log-in

Digg This Thread

Posting Permissions

  • You may post new threads
  • You may post replies
  • You may not post attachments
  • You may not edit your posts
  •  
 

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95