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Monster 695 - Rich One Cylinder, Smoke Exhaust And Very Hot!

Discussion in 'Technical Help' started by Plasticmorph, Mar 17, 2020.

  1. if moisture is going to gather as a result of long-term standing then you can expect to see it more likely in lowest catchment area partly due to gravity. If you ever strip a car gearbox after similar storage and carefully inspect the bearings, the rusty needles or balls will mostly likely be at "6 o'clock" if untouched.
     
  2. So determination continues... I’ve ordered a pair of barrels and pistons from the states and have new rings and dowels etc on order. Fortunately the barrel seems much more willing to come off the engine than the head was. The barrel and pistons are coming from the same donor bike as the new heads, so a shame I didn’t just order those in the first place and save myself some money! I expect with covid at its current state, there will be some delay to delivery so I’m debating installing the new head to see if that solves any of the problems. My thinking here is that the cylinder damage is only going to continue to damage itself and I can deal with that when the new parts arrive. Please let me know your thoughts on this! I just can’t foresee any further damage occurring if it’s ridden lightly.

    I’m guessing the lost material on the cylinders would likely be metallic and magnetic which might explain the additional material found on the sump plug at the last change.

    I’m sat here at my desk with the head in pieces and can’t really fault the intake valve despite that one making the contact. I’ve upturned the head and filled the hemisphere with water and surprisingly, the exhaust valve was the one that let it through. Just a dribble but I guess enough that exhaust gasses could have been coming out during the compression stroke?? May explain the smoke. I’ve hi-lighted some observations with a hex key. I’ve pointed to an area on the intake valve guide that had some wet oil on it, possibly indicating a leaky seal but I don’t know if ‘any’ amount of oil in there would be considered normal. Internet search suggests maybe a bit? I’ve also pointed out some grit. Now when we first stripped everything down before starting the bike there was some sand like substance in the air box. Cleaned it all out but clearly some of it has made it in. I suspect that one of two poblems with this engine may have been grit in the cylinder which may have gravitated down to the bottom of the barrel and caused additional wear.

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  3. hard to say from pictures but if valve is bent it looks to be only a small amount and (as you said) if valve is rotating then it's disguised easy evidence on cylinder head valve seat, so for a rough guide, you now need to study valve itself where it seats to see if a portion of it's perimeter looks as though it hasn't been touching seat in head during your two tankfuls plus (as has been said) you can get a crude idea from rolling on a bench. Again, not for certain, but looking at deposits on valve seat in cylinder head it looks as though engine has stood a long time in a bad environment.
     
  4. I repeat my earlier comment, grinding paste will show weather the valve is seating, do not rebuild and run with that barrel, you're asking for trouble.
     
    • Agree Agree x 1
  5. It should show on the valve contact face, not the head, more effective than rolling the stem and trying to see it wobble.
     
  6. Thanks for the advice, I’ve ordered a lapping kit but it could be a while before it arrives.
    I’ve just had a thought, I noticed earlier that the cylinder and piston had a corresponding letter and from the service guide I’ve learned that there is three different sizes. Mine is A. I don’t know what size the new ones coming are. If they’re at different ‘class’, does that mean that I absolutely must replace the vert with a corresponding letter or can the horizontal and vertical be different?

    I’ve also ordered a pair of ring pliers to remove and install new rings. My Haynes manual indicates that I first install the piston on the rod, and then slide the barrel on. It recommends using finger tips to individually pop the rings into the barrel but I’ve seen videos online showing people using a sleeve. Is the finger tip method acceptable?

    Also, is 15/50 oil acceptable as an assembly lube for these parts?
     
  7. Your replacement piston and barrels will be matched with letters as your existing ones are, keep them matched, I have had no problem fitting piston rings into the barrel with finger but be very carful as the rings are very brittle, using engine oil to lubricate on reassembly should be fine.
    Steve
     
  8. When fitting the pistons make sure the ring gaps are equally spaced, not all together, and try to avoid having a gap directly on the thrust side of the piston.
     
  9. JFTR:_ Grinding paste will not always easily show up that a valve is bent if the distortion is only slight and it can still takes some reading of the valve face to confirm.

    It wasn't me, but I don't think the person that said it first was offering this up as a definitive method but both methods have their place just for checking purposes only and no need for anyone to see it any other way. Both are crude and will always be a D.I.Y. substitute for offering it up in a valve refacer and doing it properly.
     
    #69 Chris, Mar 28, 2020
    Last edited: Mar 28, 2020
    • Agree Agree x 1
  10. Hi all, just a quick note to say thanks for all your detective work and advice. Bike is back together and although I can’t really get out and test it yet, it seems to be running ok.

    For an absolute novice like me, working on an engine solo is pretty scary so the input that I’ve had from this forum and it’s guests, is hugely appreciated.
     
    • Like Like x 3
  11. Well done, hope all's well.
    Still be interested in whether the valve was bent.
     
    • Agree Agree x 1
  12. Thanks! Just the other day I went over the old head to see what was going on and I really can’t see anything wrong with the valve. I’ve rolled it along a very flat piece of glass and lapped the valves. The combustion chamber seems to hold fluid. I realise none of that is absolute but it seems so suggest all was ok with the head end.

    I’ve recently used the bike to do a couple of journeys that I’d have otherwise been doing anyway and found that the engine seems ok but not completely without fault. The first run was short and there was a bit of blue smoke from the exhaust. Very little though and it’s cleared up so I’m assuming that was just whilst the rings were seating. On some good advice I switched away from fully synthetic which probably helped. What I am noticing is more in the way of burbling from the exhaust and occasionally when the revs are in the 2-3000 band it spits through the intake. I think it was sufficient that it blew one of the throttle body hoses off. That’s secured very tightly now and it isn’t as audible but seems to still be there. It’s interesting because I’ve found a number of threads about this being a common feature of mid 2000’s Ducati and my partners bike has been known to do it however I swear that before all these issues with the engine it wasn’t doing it. Maybe I just missed it and didn’t put a hose back properly which meant that it became obvious. As an experiment, I’ve ordered a ‘rapid bike easy’ unit. It’s one of these that sits between the o2 sensor and ECU to make it think it’s running lean so it richens the mix. I’ve heard reasonably good feedback on BMW and Ducati forums. My concern however is that if it works it will just hide an existing issue. Update to follow.
     
    • Useful Useful x 1
  13. One final blab and then I’ll call it a day on this. I’ve done circa 100 miles on the bike since replacing the horizontal ‘everything’ and it still seems ok. I’ve just dropped the oil and replaced with fully synthetic and been for a ride and all is well. The rapidbike easy definitely gets my thumbs up. I assume it’s similar to a fat duc which I didn’t know about at the time of ordering. It’s very clear that once the device registers o2 sensor temp is up and it starts to work, the intake pop goes away. The bike seems to run about 5-10’c cooler and isn’t so rich that the plugs are blackening. When the bike is open loop the pop is still present.

    Over the last week I’ve also been reading up on the air bleed screws on the throttle bodies. I checked mine and found them to be 1.5 turns out on horizontal and 2.25 turns out on the vertical. It seems from what I’m reading that this is excessive as lots of recommendations for around 0.5 to 1 turn out. Some even suggest they should be all the way closer. I’ve set mine to 1.25 out on each side and whilst the intake pop is still there when the bike is warming up, it’s significantly less noticeable. If I wasn’t looking for it, I possibly wouldn’t notice it at all. I might go to 1 turn and see what that does but I did read that could make the idle fuel mixture too rich.
     
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