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nicrguy1966

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Posts posted by nicrguy1966

  1. GT6 Mk3 only runs well with VERY advanced timing. Any ideas why?

    in Electrical System

    Posted

    2 hours ago, Pete Lewis said:

    so you know your CDSE carbs are adjusted by sticking a long allen key down the dashpot tube  there are special silly priced tools to do this

    but if you remove the air piston you can use a key down the dashpot tube  the art is a std setting that the small delrin washer on the head of the needle should

    be level with the base of the air piston  thats the starting point .    the key turns a fixed threaded ( Nut) and rotation will raise or lower the needle 

    if you have temperature compensators ( small plastic covered unit ) on the side this needs to be twiddled remove its cover and turn the small nut to 

    close the plunger  SHUT you dont need this emission aggravator  

    ie it bleeds air bypassing the throttle so if its open when it should be closed you cannot set the idle mixture ..ever.

    just something else to dream about Ha !!

    Pete

    I have one of those expensive tools somewhere, but I have no idea where. My garage is like an Aladdin's cave of treasure.

  3. GT6 Mk3 only runs well with VERY advanced timing. Any ideas why?

    in Electrical System

    Posted

    I went for a drive. To start it was a bit sluggish, but I did a roadside adjustment of the ignition timing (by ear) and it improved.

    I was only driving to warm up the engine so I could get the strobe out and set the timing, but while adjusting the distributor, I noticed a drip from one of my hoses, so I had to go back to Halfords for a new jubilee clip. Now I can't do anything until the engine has cooled down again and I fit the new hose clip.

    Final checks and adjustments tomorrow. So far the verdict is that it isn't any worse than before, and I might have a little more power in the mid range (2500 to 3500). Also, one of my tappets is making a lot of noise, so another job for the future 

    • Like 1

  8. GT6 Mk3 only runs well with VERY advanced timing. Any ideas why?

    in Electrical System

    Posted

    24 minutes ago, johny said:

    yes and quite a bit of tolerance on the figures as well. Anyway when is the big start up?

    After lunch if all goes well.

    I'm thinking of starting it up without a radiator or fan, just for a few seconds. If it doesn't start, I'll try a few times with different ignition timings, and if it still doesn't start, I'll have to consider reversing everything I've done over the last few days!

  9. GT6 Mk3 only runs well with VERY advanced timing. Any ideas why?

    in Electrical System

    Posted

    38 minutes ago, Iain T said:

    It is natural to suspect cam timing and I'm sure now you've corrected the minor error it will be better. I can only relate my experience which given the head etc required a lot more fuel and timing wasn't the problem. If you lack power after getting it back together try turning the carb adjuster half a turn and ignition at 13 degrees. I think you have a Mk2 which if your engine is standard has 6AC needles. 

    It's a late Mk3, and I don't think there is any manual adjustment on the carbs. Changing the needles is the only way to change anything (and fixing any possible leaks around the inlet manifold). 

  11. GT6 Mk3 only runs well with VERY advanced timing. Any ideas why?

    in Electrical System

    Posted

    14 minutes ago, Iain T said:

    OK a curve ball which may be a load of rubbish. In the search of 500bhp and 1000ft/lbs of torque out of my tuned Vitesse engine I tried timing it using the manifold vacuum technique. I was surprised that at tick over it did indeed run fine at around 20 degrees advance but did pink a slightly under load. Then I read or someone on the forum posted that with K&N less restricted air filters the vacuum at tick over is effected so I returned to 13 degrees. However at that setting the engine was nowhere near as good as it should be. In fact on a rolling road power dropped like a stone over 4000rpm. 

    The answer was leaky carbs/gasket joint and more importantly getting the correct needle and mixture! I've posted in fuel section my woes but now it's 95% correct the difference is huge absolutely transformed the performance and timing back to 13 degrees. 

    Iain 

    It's amazing how an odd ignition timing can lead in so many different directions! Cam timing, warn distributor and now fuel/air mixture!

  13. GT6 Mk3 only runs well with VERY advanced timing. Any ideas why?

    in Electrical System

    Posted

    1 minute ago, Iain T said:

    Does it tick over OK at say 6-800 rpm?

    Yes, lovely and smooth. I can slow it down to about 500rpm without any issues.

    The problems occur at >3000rpm where it lacks power (probably due to the spark being stupidly advanced).

    With ignition set to 13 BTDC at idle (the Haynes Manual recommended setting, but very different from the numbers provided above), it lacks power at all revs.

  17. GT6 Mk3 only runs well with VERY advanced timing. Any ideas why?

    in Electrical System

    Posted

    22 minutes ago, johny said:

    If the springs are weak or broken youre going to get too much advance but true the mechanism could be stuck so needing more initial advance to compensate. However this was suggested at the beginning of the thread and discounted😒

    They aren't stuck, the vacuum advance and centrifugal advance both do something, this was tested.

    Whether they're doing the right amount of advance at the right time is not possible for me to test at home.

  21. GT6 Mk3 only runs well with VERY advanced timing. Any ideas why?

    in Electrical System

    Posted

    2 minutes ago, JohnD said:

    OH!!!!   Inspection is useless! Just as is resistance, if you are a prisoner of the Vogons.     You cannot tell by looking if the inertia ring has moved!  I have several examples to demonstrate this!   

    When you can, refit the damper pulley.   Move the crank to TCD , as determined by a piston stop.   THEN look at the crank pulley.      If it coincides with the pointer on your timing cover, I will eat my hat (the chocolate sponge one), and resign from the Dishonourable Order of Gurus!    Nothing else can remove the suspicion that you are trying to time the ignition from a fictional TDC point and I thought you had said that you had done this, and that the TDC marking and actual TDC coincided.   

    John  

    I had already checked the TDC mark against piston 1 being at it's highest point.

  22. GT6 Mk3 only runs well with VERY advanced timing. Any ideas why?

    in Electrical System

    Posted

    7 minutes ago, johny said:

    wow yes it has progressed well! The stripped bolt is unfortunately really common as theres a bridge piece over number 1 main bearing and its made of aluminium☹️ Theres two sump bolts and one timing cover bolt that go into it and any/all strip over time - its so predictable that you can now get the same piece made in steel. An alternative is to drill and re-tap the existing holes to a bigger size because otherwise, as you have found, it will always leak.

    You rotated the engine by hand did you, right round, and rechecked the timing? With the fan bolts are you sure theyre the right ones and not got mixed up with a different thread type?

    I doubt I turned the engine right round, not deliberately anyway, but it was moving backwards and forwards quite a bit when I was tightening the cam gear bolts and I turned the engine the right direction back to TDC and checked the balance point after tightening.

    The fan bolts are definitely the right ones. I kept them with the fan. Two fit, two get stuck after 1 turn. Frustrating, but with fresh fingers I'll have another go very soon.

  23. GT6 Mk3 only runs well with VERY advanced timing. Any ideas why?

    in Electrical System

    Posted · Edited by nicrguy1966

    4 hours ago, johny said:

    As I say this next step may need a few attempts so dont go giving anything its final tighten just yet...

    I think it only took me 10 or 11 attempts to set the balance point, set TDC, put the cam gear and chain on, check balance point, check TDC, tighten bolts on cam gear, check balance point, check TDC, remove cam gear and chain, set balance point, set TDC, put cam gear and chain on, check balance point and TDC, etc, etc, etc!

    Anyway, I'm happy now. In the end I had to flip the cam gear over, but I have no idea if it's 1/4 or 3/4 of a tooth different from when I started. The important thing is that the cam is at the balance point when the crank is at TDC and all the bolts are tightened.

    Two problem during the reassembly process. First, one of the bolts that holds the timing chain cover on just goes round and round. I don't think I stripped the thread as I never even got as far as tightening it with a wrench, I was just screwing it in by hand and discovered the problem. Even more anoying, it near the bottom so might explain the oil leak my car has always had from the front of the engine.

    Second, I can't get 2 of the bolts in that hold the fan on. They get stuck after about 1 turn. I tried screwing them in without the fan and all the rubber and steel sleeves to see if they were causing the problem but they weren't. Two screws are just refusing to play ball.

    I was very tempted to try starting the engine without a fan or radiator just to see what happens, but I thought I'd sleep on that idea and maybe give it a go tomorrow.

    I also still need to reset the rocker gaps on valves 1 and 2, but overall, excellent progress today (assuming the engine starts!).

    • Like 1

  24. GT6 Mk3 only runs well with VERY advanced timing. Any ideas why?

    in Electrical System

    Posted

    4 hours ago, JohnD said:

    I think I suggested a shifted outer ring (inertia ring) on your crank damper pulley, which was my first thought, but you found that it was a true indicator of TDC.

    Other than that, it is possible to install the distributor drive 180 degrees out - the drive slot is only slightly offset - but that would need VERY advanced timing!

    Now you have corrected this small cam timing fault, please try the engine and prove me wrong!

    John

    With the crank pulley off, I had a very good look at it, and there's no sign of any movement between the pulley and the rim with the timing marks. I'm even more confident now than at the start of the job that the TDC mark is in the right place.

  25. GT6 Mk3 only runs well with VERY advanced timing. Any ideas why?

    in Electrical System

    Posted

    46 minutes ago, JohnD said:

    I think I suggested a shifted outer ring (inertia ring) on your crank damper pulley, which was my first thought, but you found that it was a true indicator of TDC.

    Other than that, it is possible to install the distributor drive 180 degrees out - the drive slot is only slightly offset - but that would need VERY advanced timing!

    Now you have corrected this small cam timing fault, please try the engine and prove me wrong!

    John

    I haven't quite fixed the timing fault yet, but thanks to the help of several TSSC members, I'm well on my way.

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