VW 1800 AW code engine cylinder head cracked need help.

Discussion in 'Mech Tech' started by shahaviation, Sep 18, 2015.

  1. Having one and finding one are entirely different !! :thinking::)
     
    nicktuft likes this.
  2. New update and more problems. Finally the new engine is being assembled at last but more snags. The existing heatexchangers won't fit in the 1800AP unit supplied by heritage. The attaching holes to the engine are not aligning with the studs. The mechanic has attempted to modify by enlarging the holes from 8mm to 10mm and still half a hole out on two studs and does not want to enlarge the holes any more as they will be too near the edge. This is on both sides. Does anyone know if the heatexchangers are different from the old AW engine or indeed if there is a difference between the 1800 to the 2000 units. Heritage can't understand why the old units won't fit and am goeing to get pics tomorow so I can show them the problem. Any help would be good from you experts as it looks like I will have purchase new exchangers at great cost.
     
  3. @zed has mucked around with 1800 heads i believe - once again , he` the `go to` man .... :rolleyes:

    :hattip:
     
  4. Zed

    Zed Gradually getting grumpier

    I tried and failed to furnish myself with a pair, then settled for 10 a penny 1700 heads. Why nobody wants these is a mystery, the inlet valves are only 1mm smaller diameter.
     
  5. MorkC68

    MorkC68 Administrator

    What heat exchangers have you got, are they genuine or reproduction?

    Ive just built an AP motor with AMC Heads and repro heat exchangers (heads/exchangers bought from Heritage) and they was a tight fit to start with but they went on easily once a small round file cleaned the slots out
     
  6. 77 Westy

    77 Westy Supporter

    And the ports are the best of the bunch for flow. 1700 valve sizes are 39.3 x 33, 1800 are either 39.3 x 34 or the sought after 41 x 34.
     
  7. I'm sure a 1700 with a decent 3 angle valve job and a bit of fettling would flow better than bog standard 1800 big valves .


    Ref the op . If you measure the stud centres on your heads I'm sure Paul @Paul Weeding would confirm if it's heads or HX
     
  8. 77 Westy

    77 Westy Supporter

    Correct.
    Or the mechanic.
     
  9. Zed

    Zed Gradually getting grumpier

    Mine have had what to me is a mental amount of fettling. The ports from one end to the other are like a long venturi smoothed into the valve seat. I suspect Rob may know what he's doing. :thinking:
     
  10. Here is pic showing the measurements that i sent to Heritage to see what they suggest. Its a 6mm difference .
    New Engine dimensions.JPG PC182683.JPG PC182691.JPG PC182688.JPG New Engine dimensions.JPG PC182683.JPG PC182691.JPG PC182688.JPG PC182686.JPG
     
  11. I'll measure up an old set of heads to see what's what. ..
     
  12. Many thanks Paul.
     
  13. Zed

    Zed Gradually getting grumpier

    I had a measure of a heat exchanger earlier for you.
    The spacing on the outer and inner side of the engine are different.
    I made it 174mm and 184mm. I can't remember which way round. :oops:
     
  14. Zed

    Zed Gradually getting grumpier

    This could be clearer! From your pics I see the "inside" studs are further apart - 184mm.
    Looks to me your sketch shows 173 for outer heat exchanger and "approx" 189mm for inner on the head. Approx? Can we assume some exaggeration to make the point? In that case they aren't so far out perhaps.
    [​IMG]
     
  15. Thats great news Zed. Many thanks for taking the time to measure for me. Sounds like my mechanic got the wrong side exchanger to fit and did not try the other side. I will go over tomorrow and make sure he checks the other side. Must admit I did not know they were different sizes .
    The guys from Heritage also measured their new exchanger from stock and said that the spare he measured was 1 mm out from the Eng block measurement i sent so he is sending a new pair over. Guess its luck he picked up the right side. You may have just saved me some cash. Will update you tomorrow.
     
  16. Zed

    Zed Gradually getting grumpier

    He can't really fit them the wrong way round, it was more a comment that he'd measured different pairs which made it look wildly out. It doesn't take much to make them very difficult to fit though, it's all quite precise.
     
  17. You are right. I went over and rechecked and spoke to the mechanic who said the same thing. New exchangers did not arrive today so hopefully tomorow and see if they fit.
     
    zed likes this.
  18. Update. Finally got the bus back and running in begins. Had to fit new exchengers and also new thermostat and cable etc and make adjustments to tinware to fit correctly and found out the lower tins were missing altogether. We made a plate to go across the bottom so that the cooling air can flow around the engine until I can find correct replacements.
    The mechenic had problems setting up the Weber 34 ict carbs to run at 3 % rich but could not get to this .so he did the best he could and recomended to get proper set up done and rejetted on rolling road as soon as engine run in as its running lean.
    Only job remaining for me is to wire up the oil temp gauge to the dipstic sender unit supplied by JK.
    So after 6 months the van is back on the road and looks like I will running in the enging on the way to volks world next week.
    Would appriciate recomendations of a good rolling road tuning shop around luton area or as close as possible.
     
    Iain McAvoy and Paul Weeding like this.
  19. finally run in the engine and still running hot. Around 120 to 140 C. Had rolling road tune done and produces 94BHP but with servo vacume pipes blanked off at the carbs as leaks detected. Also hydrocarbons high and could not get them down. Tuning guy suggested it may be tight tappets or cylinder pressure. Mechanic had already reset tappets and changed oil prior to rolling road and still running hot on way home. Checked servo pipes and found leak and fixed it. Also got the correct RH undertin from heritage after 3 week lead time and now fitted. Looking for the LH undertin now. Van back in garage for compression check and rebalance carbs again due to reconnecting servo pipes on carbs and also recheck tappets . Can't give up now as too far in and determined to solve hot running problem. The van ran great on way to garage so we now wait for results of compression test. Hopefully tomorow.
     
    nicktuft likes this.

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