john milner Posted November 23, 2015 Author Share Posted November 23, 2015 The cast lump is apparently an "evaporator". Divided opinion on if having one is a good idea or a bad one.http://forums.mg-rover.org/showthread.php?t=458366 Link to comment Share on other sites More sharing options...
revilla Posted November 23, 2015 Share Posted November 23, 2015 Yes I've seen pumps with and without. I think the idea is that any water leaking past the seal is caught in there and evaporated away by the heat from the block rather than going into the belt. Just read that thread and yeah I can see the arguments both ways.If you have the evaporator on your existing pump, there should be a big shoulder bolt going through it, basically an M6 thread on the end that acts as one of the bolts to hold the pump in place then a long pillar that sticks out through the front rubber bush in the evaporator and has a 13mm hex section to allow you to tighten it and is drilled to accept another short bolt that secures the bottom corner of the belt cover.If you have the evaoprator and rubber bush but just an open hole in the fron of it without the special bolt I would say it was doing absolutely nothing.And yes .. rotate the crank to align the marks before assembling. You should notice it running better too. Only turn the crank the "short way" to line them up. You can turn it both ways if you overshoot a bit. Don't turn it right around as the cams will not be moving with it so there is a risk of piston / valve contact. With the marks lined up correctly it is in "safe position" so all the pistons are half way up (or down!) the bores and miles away from the valves. Plently of room to wriggle it round into line safely. Link to comment Share on other sites More sharing options...
revilla Posted November 23, 2015 Share Posted November 23, 2015 You should have one of these through the evaporator. Link to comment Share on other sites More sharing options...
revilla Posted November 23, 2015 Share Posted November 23, 2015 Sorry I really should collect all my thoughts before posting and do it in one go ... if you just have a normal bolt buried at the back of the evaporator you should be able to just pull the rubber bit out and remove the buried bolt, then re-use it for the new pump without the evaporator. The only thing that holds the rubber bit in is the shaft of the special bolt shown above. Link to comment Share on other sites More sharing options...
john milner Posted November 23, 2015 Author Share Posted November 23, 2015 Four bolts loose and no sign of the pump shifting without violence.Rubber plug removed and photo taken of what is inside. Even with a 12M image blown up I can't work out if there is a bolt head or funny valve. Link to comment Share on other sites More sharing options...
john milner Posted November 23, 2015 Author Share Posted November 23, 2015 Just realised something. When I loosened the lower cover bolt it wouldn't loosen but came away stuck with the cover. I probably removed the evaporator bolt ages ago and have been wasting my time looking for it.Time to remove the four other screws completely and give it a gentle wack. Link to comment Share on other sites More sharing options...
revilla Posted November 23, 2015 Share Posted November 23, 2015 Looking at that photograph I would say what you can see there is the threaded end of the evaporator shoulder bolt sheared off in the block . Your water pump appears to be then just held in place by the four remaining bolts. It that's the case you may be able to get the stump of the bolt out once the pump is off, you may have to live with it if you can't - in which case the evaporator / no evaporator question becomes completely academic because the evaporator won't be doing anything with the big bolt missing anyway.Once you have removed the remaining bolts, there are two dowel pegs (I think, from memory) that locate the pump. There's a rubber O-ring rather than a gasket, so that won't be sticking it to the block but it could be stuck on the dowels if it is a bit corroded. Gently tapping with a soft mallet should loosen it off, by try to tap it in such a way that you are knocking it forwards rather than sideways otherwise all you are doing is straining the dowels.When you put the new pump on, stick the new rubber O-ring into the groove with a smear of silicone grease and make sure it doesn't move out of place. Link to comment Share on other sites More sharing options...
Mankee Posted November 23, 2015 Share Posted November 23, 2015 There is also a bolt going backwards through from the cambelt cover side into the water pump, near the top. Link to comment Share on other sites More sharing options...
SM25T Posted November 23, 2015 Share Posted November 23, 2015 I think I recall one bolt comes from the rear !!!! Please check before using force ! Link to comment Share on other sites More sharing options...
revilla Posted November 23, 2015 Share Posted November 23, 2015 I think the bolt from the rear is just for the plastic belt cover. Link to comment Share on other sites More sharing options...
john milner Posted November 23, 2015 Author Share Posted November 23, 2015 I spotted the rear bolt as soon as I managed to free the pump. Very fiddly to undo and do back up. I have a ratchet spanner but it took a lot of toing and froing.The shoulder bolt had sheared and had less than 1/4" sticking out the block but fortunately I managed to undo it with pliers. I have fitted a standard bolt for the time being but I need to get the correct bolt or I'm going to have a flappy upper cover next to the belt. I think the original must have been very close to bottoming out in the hole which may explain the shearing. I have cut the new bolt slightly shorter than the original.The new pump has a rubber cap that goes over a channel in the casting. I'm guessing that this may be a cheapo version of the evaporator. I stuck it on with blue gasket sealant. Not sure if this is a good idea or not as there is a risk of it coming off and getting caught in the belt.My next job is to get to the bottom of a heater leak while the system is drained so you may see me pop-up in another thread shortly.Sheared bolt: New pump v old: New evaporator?: Part number of pump (metal impeller) included with Gates kit from Ebay: Link to comment Share on other sites More sharing options...
revilla Posted November 23, 2015 Share Posted November 23, 2015 Glad to see you are making progress. The great thing about mucking in and getting your fingers dirty doing jobs like this is that you learn so much every time. Link to comment Share on other sites More sharing options...
john milner Posted November 23, 2015 Author Share Posted November 23, 2015 Rimmer Bros do two types of pillar/shoulder bolts. PEW100070 for £6.20 or PEW100070L for £3.96 which has the message "USE PEW100070". Any idea if these parts are interchangeable?As I've not got the pucker evaporator on the new pump is there a different bolt I should be using? The Rover/Elise manuals I have show a pillar bolt without an evaporator but no part number. Link to comment Share on other sites More sharing options...
revilla Posted November 23, 2015 Share Posted November 23, 2015 I think you still need the same bolt as you need it to attach the front belt cover. The "L" suffix on the part just means it was sourced through Land Rover, entirely interchangeable (and probably identical). Link to comment Share on other sites More sharing options...
revilla Posted November 23, 2015 Share Posted November 23, 2015 Got this in my spares box. Not too pretty but will save you the Rimmer postage. If you want it you can have it. Just BM me your address and I will stick it in the post. Link to comment Share on other sites More sharing options...
john milner Posted November 23, 2015 Author Share Posted November 23, 2015 YHM Link to comment Share on other sites More sharing options...
jackb_ms Posted November 24, 2015 Share Posted November 24, 2015 About replacing belt, on Car SOS last week, when working on a Nissan GTR, one of the mechanic sliced the old belt in half long ways then slide the new one on then finaly cut the old one off.Is that another solution? Or it should not be done in this way?Jack Link to comment Share on other sites More sharing options...
john milner Posted November 24, 2015 Author Share Posted November 24, 2015 Slicing a belt sounds awkward although it may have saved the £3.48 I spent on a locking tool. I haven't fitted either new belt yet but now I have everything in bits it looks easy. Perhaps a GTR has some special issues with keeping or getting correct alignment. Link to comment Share on other sites More sharing options...
revilla Posted November 24, 2015 Share Posted November 24, 2015 In your case it might have been a bad choice of method; doing it this way you have discovered that the original belt was apparently installed misaligned by one tooth at the crank. If you had sliced the belt and just duplicated the timing you would not have corrected this. Link to comment Share on other sites More sharing options...
john milner Posted November 26, 2015 Author Share Posted November 26, 2015 I did about 30 miles today with the new belts and the engine feels more responsive. I even stalled it a couple of times on the drive so I don't think it is my imagination. It's almost as though a very minor clutch slip that I didn;t know I had has been cured. Could one tooth being out on the old belt or less slack/stretch in the new belts be the cause? It was a bit disconcerting at first as I was expecting no improvement as I don't recall any difference after a a garage did the last belt change. Link to comment Share on other sites More sharing options...
SM25T Posted November 26, 2015 Share Posted November 26, 2015 It will be a tooth out before rather that old belt stretching. Enjoy. Link to comment Share on other sites More sharing options...
revilla Posted November 26, 2015 Share Posted November 26, 2015 There are 24 teeth on the crank pulley (48 on the cam pulleys).Each tooth is therefore 360/24 = 15 crank degrees.From your pictures, all of the cams had reached their timing marks before the crank had reached its mark (rotating clockwise) so the cams were all advanced by 15 crank degrees.In performance terms, that's a big difference. I think Dave Andrews reckons they naturally run a few degrees retarded from their optimum positions which is why he supplies offset dowels, but I think usually by around 4 to 6 crank degrees, so advancing them by 15 would leave them in the region of 10 crank degrees too far advanced. You will notice the difference I'm sure.And yes the one tooth error is way more than you would get from belt stretch.Enjoy! Link to comment Share on other sites More sharing options...
john milner Posted November 26, 2015 Author Share Posted November 26, 2015 Very surprised that one tooth adds up to so much but the maths now make sense of why. Oily said on a post somewhere that the timing can be out by 70 degrees before a valve hits a piston. As a number that sounded a heck of a lot to me but it means that just four teeth out is the limit and obviously anything in between is not going to run quite right. Link to comment Share on other sites More sharing options...
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now