New Engine Rebuild

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  • #233816
    MGLondonRoadste
    Participant

    @mglondonroadste

    After discovering that the GEX engine that came with my London Roadster back in May was trashed (dirty engine, scarred up), I found a good 1600 block from 1971 and had it punched out to 1835cc.  My neighbor is helping me, or should I say that I might be helping him to rebuild the motor to new specs.

    Hopefully the machine work on the block is done today and it can come home to begin the rebuild.

    #247800
    Paul Mossberg
    Keymaster

    @pmossberg

    Nice. Share the build with us!

    Pictures, captions….would be very educaitonal for a lot of people!

    Paul Mossberg
    Former Owner of a 1981 Classic Roadsters Ltd. Duchess (VW)
    2005 Intermeccanica Roadster

    If you own a TDr and are not in the Registry, please go to https://tdreplica.com/forums/topic/mg-td-replica-registry/ and register (you need to copy and paste the link)

    #247801
    edward ericson
    Participant

    @edsnova

    I’d like to hear more about the GEX too. I have heard some unflattering things about them. Was your engine new & came “scarred up” from the builder?

    #247802
    MGLondonRoadste
    Participant

    @mglondonroadste

    When we decided to try to punch out the GEX engine we tore it down and tested it to see it it would handle the increases size.  The block was magnafluxed and when everything was opened up, we found pitting and cracks.  The engine was toast – “a paperweight”.  Apparently is was left dirty when it was rebuilt by GEX and that resulted in a trashed engine.

    So I bought a new block and started from scratch.

    #247803
    Marc Lipsius
    Participant

    @mrlmd

    No warranty or quality control on that? They shouldn’t sell something like that, but you didn’t buy it from them so I guess you got stuck.

    #247804
    MGLondonRoadste
    Participant

    @mglondonroadste

    I bought the car used and out of state without seeing it in person and had it looked at by a repair shop in the area that worked on VWs.  There is no way even the shop I hired in the local area would have known the problems unless they took the engine completely apart and magnaflux tested it, which wasn’t what I asked them to do.  The engine ran enough to get me from Seattle to Phoenix (almost)  I had to be towed the last 50 miles home, and made 3 repair shop stops along the way.  They did check it out, even though they did not do the compression test I requested and it got me running.  I have a write up on that trip in another thread.

    #247805
    MGLondonRoadste
    Participant

    @mglondonroadste

    I had a chance to see the new (used, of course) 1600cc block at the machine shop before any work was done to it.  I was either misinformed or misunderstood, thinking that I would be assisting in the engine re-assembly this past weekend.

    It’s not perfect.  There is a threaded bolt (1 of 4) hole next to the hole in the block for the cylinder head.  One of these holes is stripped and will need to be machined out slightly to accomodate a sleeve so that it can be re-tapped.

    Then the cylinder head opening will need to be machined to allow the larger heads.  This increase in diameter will come very close and may eat into the threads of the re-tapped bolt hole.  This would result in oil leakage through the cylinder heads, which is something I don’t want.

    I’m going to go ahead with the machine work and hope the clearances are still good enough for the head enlargement and the bolt hole re-tapping.  This block only cost at $225.00 and the one the shop wants to sell me is going for $700.00 right now, and it would still only be a 1600cc that I’d want to punch out to 1835.  I could be out the block and machine work if it all fails, but I’m going to try this less expense path first.

    My crank shaft is in good to fair condition, having a current rating of what the shop called a “30”, meaning 30% already machined away.  I’m told it will work for now, but can’t be remachined any more.  We’re getting the bearings to fit it as it is now.

    The shop that is doing the maching work is known for good quality work, but not speed.

    So, last week, I thought I would have my London Roadster ready by Thanksgiving.  Now I’m not sure when it will be running again.

     

    #247806
    edward ericson
    Participant

    @edsnova

    This does not sound promising . . . .

    #247807
    MGLondonRoadste
    Participant

    @mglondonroadste

    My neigbor mechanic is guarenteeing the work, so if I have trouble with it, the fix is out of his wallet.

    #247808
    edward ericson
    Participant

    @edsnova

    OK then. But a fair number of folks who know more than we do have set general suggestions for engine building that I have, myself (and with unhappy results), tried to defy.

    The basic formulation goes about like this: if you want to build something out of junk (aka well used engine blocks or cases; cranks with .030 already turned off them, previously decked heads, etc) you can do it very well, provided that what you’re seeking to make is a pretty low-horsepower, workaday-type engine of the kind that you run in your beater whilst saving up for the “real” engine. Go cheap, put a lot of skill into the effort, and don’t expect much. That works.

    Conversely, if you want to build something high performance, you can do that, if you are prepared to pay for top-notch (i.e. new, expensive) parts. You put a goodly amount of time and highly-skilled effort in with your money, you’re likely to come out with an engine that can run, as they say, with the big dogs.

    BUT.

    Try to build something jazzy out of junk, and you will very likely be disappointed.

    This is not a rule I’m just making up right now. It’s not even a rule I have, in the past, held any allegiance to. It just appears to be something like a law of nature.

    Now I know there are many people–many VW people–who would consider a Type1 with 92mm jugs to be nothing special. Non-high-performance. And maybe they’re right. But given the case machining going on here, and given the stripped out bolt hole–one of the holes that actually hold the cylinders and heads to the case–I think I’m not being unduly radical or buzz-killing here to say:

    If it were me I’d think about going to a new case…or to maybe an 87mm cylinder kit.

    This would be doubly true if I already had another car just like the one whose engine rebuild was under consideration except it had 300 bloody horsepower.

    edsnova40868.8356365741

    #247809
    Royal
    Participant

    @royal

    Hey guys, I am looking for a winter project/hobby.  First let me say that I have overhauled 3 diesel engines and a few gas engines including 2 VWs but that was long ago.  I am considering buying an engine and fixing it up as a spare.  I have had spare engines before and I really like having a good one ready to plug in.  (MIGI’s current engine is a stock 1500 that runs pretty great.) 

    So, here’s the deal:  I live very close to a gent who restores VW’s and has 104 T1 bugs on his lot that I counted.  Also 3 or 4 Ghias. They have all been sitting there for years and are only spare parts cars.  I told him what I was hoping to do and he recommended a 1970-1974 DP engine.  After some arm wrestling, he said that he would give me one that was complete including exhaust and carb, etc for $400.  He is going to pull it out.  He would not guarantee that it would run.  I insisted that we be able to roll it over with a wrench, he said ok. 

    Question:  1.  I am hoping to get a running engine for $1000 (the initial $400 + another $600 in parts).  Is this possible?  2.  What would you check for before purchase?  3.  I expect to take it apart and carefully inspect it, replacing bearings and rings and valves as necessary.  Are there any big snakes in the grass that I might be able to detect before pulling the engine?  I think that I may pretty much get my choice of 20 or so engines.  Please don’t forget that I am limited in funds to about $1000 for another 6 months or so.  It is possible that if I run into some big unexpected expense, I will not complete the project for another year.  4.  How would you spend your $1000?  If you think that it would be a waste having it apart and not putting on bigger jugs and going to 1800cc, please tell me and perhaps I will still buy it but put a longer time line on my project.  I am happiest with a wrench in my hand.   I don’t have any interest or intent in racing it.  Prefer reliablity and long life over performance (but will admit to being somewhat of a hot rod when the top is down).

    #247810
    Scott A Chynoweth
    Participant

    @1oldbuzz

    I am no expert,But I do know crankshaft end play is a consern.Grab the belt pulley and tug and push on it and see how far things move.On an engine with high miles there will be play,some is normal,but if it has too much,this meens the thrust bearing suface will need machining and most likley an align bore for the crank.

    Keep in mind the more you go over a 1641 requires more machining,the case will need bigger holes for the jugs as well as fly cutting the heads.

    you could also go with the 1800 type 2 3 and convert to a type 1.Takes a bit of doing but has been done

    #247811
    newkitman
    Participant

    @newkitman

    What 1oldbuzz said is true. Crankshaft end play will be a good indicator. Also try to get an engine with a doghouse shroud. This allows better cooling for the engine and oil. Another are to check is the front side of the case right behind the flywheel. Some older cases crack around the 3 o’clock position (as you face the flywheel). If the case is cracked, you’re done.

    Mid america motorworks has an 88mm piston kit again. They used to make them and thats as big as you can go without a lot of mackining on the case and heads. Also there are a number of parts houses that sell engine rebuild kits. I get mine from either mid america or cip1.

    Tear the engine down, clean it up and get it line bore checked. Even if it doesn’t require a line bore you’ll know its true and exactly what size bearings (20 over, 40 over, etc) you need. Rebuilding vw engines are fun. You have a nice winter project.

    Allen Caron
    VW based 53MGTD - "MoneyPenny"
    "If one thing matters, everything matters" - from the book The Shack

    #247812
    Royal
    Participant

    @royal

    Thanks Scott & Allen.  Hope you all have a great Thanksgiving day.  I have 2 ques:  How much end play is too much?  and What the heck is a doghouse shroud?  (geez, I sound pretty stupid asking what a doghouse shroud is.  Is this some aftermarket thing?) 

    #247813
    newkitman
    Participant

    @newkitman

    Get the Bently Manual for your year VW. I think the Orange Bentley manual is the later VW model years. It’ll cover an engine rebuild to the letter. Off the top of my head, I believe the end play limits is 0.003 but not certain. Years of engine building in the Air Force taught me never to memorize limits because they always changed. You can also check on line for the limits in http://www.thesamba.com in their technical section.

    A “doghouse” shroud has an adapter on the oil cooler that move the oil cooler to the outside of the shroud and has an added duct on the front side for the cooler. Its a stock shroud. Earlier VW engines had the oil cooler sticking up right inside the shroud and blocked a lot of cool air from flowing around the No. 3 and 4 cylinders. No. 3 cylinder seemed to suffer the most. Moving the oil cooler out of the way allowed the cool fan air to go directly to the cylinders. The added duct took a small portion of the cool air and ducted it to the front side of the shroud, through the oil cooler and vented the hot air overboard. Hope my explanation helped.

    Happy Thanksgiving to you and yours and to all our club members. Take time today to give thanks for all we have. 

    newkitman40871.4118287037

    Allen Caron
    VW based 53MGTD - "MoneyPenny"
    "If one thing matters, everything matters" - from the book The Shack

    #247814
    Larry Murphy
    Participant

    @larry-murphy

     Great advice Allen, both on the VW and Thanksgiving!!! If we stop and think about it, we all have much to be thankful for.I’m glad we still have a day set aside to keep us reminded of how blessed we are.

    #247815
    Royal
    Participant

    @royal

    Allen, I’ve got the Bently.  I guess that MIGI’s current 1500 engine has the earlier type shroud (?).  Wow, I get to use my dial indicator for the first time in many years.  Bentley says .003-.005 for end play. Thanks. 

    #247816
    newkitman
    Participant

    @newkitman

    Royal,

    Here’s a link to an engine build sheet that I’ve used for about 12 years. Helps me a lot.

    http://www.thesamba.com/vw/archives/info/engine_build_sheet. php

     

    Allen Caron
    VW based 53MGTD - "MoneyPenny"
    "If one thing matters, everything matters" - from the book The Shack

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