GHILA Posted June 11, 2021 Report Share Posted June 11, 2021 I have just put my Spitfire 1500 on the road since buying in November and restoring. I have notice a "Heavy Rattle" when the revs reach around 2500. Which is not nice to hear, I am from an engineering background and don't like knocking noises. From your extensive experience is there anything which immediately comes to mind. This does not seem to happen when standing still and lifting the revs. this is definitely an engine noise. Link to comment Share on other sites More sharing options...
JohnD Posted June 11, 2021 Report Share Posted June 11, 2021 "This does not seem to happen when standing still and lifting the revs" but is "definitely an engine noise". That does not compute, Captain. Do you mean it only happens when the car is moving? In which case this is transmission or suspension, not engine. Link to comment Share on other sites More sharing options...
NonMember Posted June 11, 2021 Report Share Posted June 11, 2021 15 minutes ago, JohnD said: Do you mean it only happens when the car is moving? In which case this is transmission or suspension, not engine. Well, probably, but not absolutely. It is possible that it's an engine noise that only happens under load, so you get it when driving but not when revving gently at idle. Link to comment Share on other sites More sharing options...
johny Posted June 11, 2021 Report Share Posted June 11, 2021 Could pinking then? Worse under load like going up a hill and when the engine is up to temperature? Link to comment Share on other sites More sharing options...
Pete Lewis Posted June 11, 2021 Report Share Posted June 11, 2021 has all the sounds of the the exhaust system is in close contact and when power is applied the tilt of the engine under torque gets the exhaust with a small clearance to make contact somewhere along its route it can be quite horrific thats where i would look this could be a cheap noise rather than 1500 with the big ends shot Link to comment Share on other sites More sharing options...
Dick Twitchen Posted June 11, 2021 Report Share Posted June 11, 2021 Engine and/or gearbox mountings shot? Link to comment Share on other sites More sharing options...
DanMi Posted June 11, 2021 Report Share Posted June 11, 2021 is it just revs or is it more pronounced under heavy throttle. Big end will knock (if worn) when you put your foot down under load but not when revved not in gear. I would first check the end float by trying to move the crank pulley forward and back, more than a couple of thou would indicate a worn engine and is easy and free to check. All of the above suggestions are also possibilities and much cheaper to fix! Link to comment Share on other sites More sharing options...
GHILA Posted June 13, 2021 Author Report Share Posted June 13, 2021 Thank you everyone for your replies but I believe that i have found the cause. I noticed that the stay bar securing the radiator was not securely fastened and after tightening up the nut/bolt. the noise disappeared. Result cost free fix. 2 Link to comment Share on other sites More sharing options...
AndyTV8 Posted June 13, 2021 Report Share Posted June 13, 2021 33 minutes ago, GHILA said: Thank you everyone for your replies but I believe that i have found the cause. I noticed that the stay bar securing the radiator was not securely fastened and after tightening up the nut/bolt. the noise disappeared. Result cost free fix. Good stuff, a great example of looking for the simple fix rather than over-thinking, well done ....... Andy Link to comment Share on other sites More sharing options...
Pete Lewis Posted June 13, 2021 Report Share Posted June 13, 2021 simple and effective gets my vote but you need to get the ears tuned to differentiate cheap from deep pockets noises Ha Pete Link to comment Share on other sites More sharing options...
Chris A Posted June 13, 2021 Report Share Posted June 13, 2021 The sort of cure everyone wants 😅 Link to comment Share on other sites More sharing options...
daverclasper Posted June 13, 2021 Report Share Posted June 13, 2021 (edited) On 11/06/2021 at 22:26, DanMi said: I would first check the end float by trying to move the crank pulley forward and back, more than a couple of thou would indicate a worn engine I gathered, that there was a always few thou of play intended, maybe around 4thou?. Also, a view that the outer limit of play specified, can be exceeded to some point?, with no harm to piston alignment, or risk of thrusts dropping out, as long as this play is monitored, so doesn't get excessive?. Interested in this, if anyone has any thoughts?. Dave Edited June 13, 2021 by daverclasper Link to comment Share on other sites More sharing options...
johny Posted June 13, 2021 Report Share Posted June 13, 2021 My Vitesse manual says 6 - 8 thou and Id imagine this is pretty standard. Reckon it has to be quite a bit more before the thrusts can drop out or damage occurs! Once set correctly you can get a feel for it by moving the pulley and then just recheck it by eye every so often. Unless the clutch has been ridden a lot its most likely the thrusts will not need changing until other work, like big end bearings, needs doing on the crank.... Link to comment Share on other sites More sharing options...
Pete Lewis Posted June 13, 2021 Report Share Posted June 13, 2021 end float you must check the workshop manual as there are differing figures for end float even on similar engines a 2.5 is less than a 2ltr for what ever reason but never guess the spec 0.002" is too tight some ae up to 0.012" they only fall out when the float exceeds the size of the lump on the bearing cap that retains it Pete Link to comment Share on other sites More sharing options...
Colin Lindsay Posted June 13, 2021 Report Share Posted June 13, 2021 I've just fitted two to the Herald engine... standard ones fitted, +5 thou didn't. They wouldn't even squeeze into the gap, not even one with a standard on the other size, so I had no choice at all. Link to comment Share on other sites More sharing options...
johny Posted June 13, 2021 Report Share Posted June 13, 2021 I wouldnt lose sleep over it Colin! If engines can run until the thrusts fall out youll have to do a lot of miles before you have a problem😆 Link to comment Share on other sites More sharing options...
Colin Lindsay Posted June 13, 2021 Report Share Posted June 13, 2021 I don't!! First time I ever changed those was on a GT6 engine which seized on first turn of the key. Seized solid after thirty seconds! We had just fitted a replacement gearbox, mate inside the car with a socket and me outside with a spanner for the other end of the bellhousing bolts. After a lot of headscratching a mate told me to whack the pulley with a lump of wood... and that freed the engine. It turned out the gearbox and crank weren't compatible - too long of a shaft tip for the end of the crank - so when they wouldn't join up completely the mate inside the car decided to pull them together by tightening the bolts. All that did was push the crank forward and immediately banjax the thrust washers. I removed the engine, turned it upside down and slid various sizes of thrust washers in and out until I reckoned I couldn't squeeze another one in. That was as precise as measurements got. We also cured the gearbox by cutting the end off the shaft with an angle grinder. It ran well until I upgraded both engine and gearbox about two years later. Link to comment Share on other sites More sharing options...
Pete Lewis Posted June 14, 2021 Report Share Posted June 14, 2021 i couldnt fit the thickness needed as the back to front thrusters had worn a good radius in the journal face this restricts the thrust fit ie why wont the thing go in ...argh its the way the crank face had been worn and getting the sump off on a 2000 is lot less faf than in a Vit/Gt6 hence the idea was get a new thrust beaded in and fit to size on the none thrust side thats been fine for 3 years now Pete Link to comment Share on other sites More sharing options...
DanMi Posted June 17, 2021 Report Share Posted June 17, 2021 Agreed a small amount of end float beyond the factory spec on a used engine is no issue but if we are talking a couple of mm that would indicate a very worn engine, hence that coupled with a "rattle" at revs could indicate a bottom end issue. If they do fall out and that has happened twice for me, then it possibly can be fixed, but better to rebuild before they drop out. Link to comment Share on other sites More sharing options...
dougbgt6 Posted June 17, 2021 Report Share Posted June 17, 2021 When I bought my GT6 I discovered the oil was turning to jelly within a month, then I noticed it had a massive end float 1/8" or thereabouts. Because the pistons are held vertical by their bearings as the crank moves back and forth, there is wear to the big ends, crank and piston bores. I replaced end floats, mains and big ends, but too late. The bores had worn in an elongated "S" shape which needed 20 thou re-bore plus the crank re-ground. So, don't leave it too late! Doug 1 Link to comment Share on other sites More sharing options...
daverclasper Posted June 17, 2021 Report Share Posted June 17, 2021 6 hours ago, dougbgt6 said: When I bought my GT6 I discovered the oil was turning to jelly within a month I guess that's an exaggeration Doug?, though did all that fine, though plenty of, metal wear make it loads thicker? Link to comment Share on other sites More sharing options...
dougbgt6 Posted June 17, 2021 Report Share Posted June 17, 2021 New oil got very thick and grey very quickly, I though exhaust was getting into the oil via the strangely worn bores. But no, not set jelly that you would accept on a plate! Perhaps thick milk shake or smoothie consistancy. Doug Link to comment Share on other sites More sharing options...
daverclasper Posted June 17, 2021 Report Share Posted June 17, 2021 Wow Link to comment Share on other sites More sharing options...
GHILA Posted June 18, 2021 Author Report Share Posted June 18, 2021 Good morning Gentlemen, well I thought that I was lucky but alas NO. Still wasn't happy with engine so under I go. Result after removing Main bearing cap is bearing material gone and through to copper. The journal itself looks good, next step pull the caps off the big ends to see what they look like. Hoping to replace just shells if I am lucky. Does anyone know if the Main shells can be removed with engine in situ. Using copper pin in oil hole perhaps and rotating crank to push out shell ??. Once again replies appreciated. Link to comment Share on other sites More sharing options...
Clive Posted June 18, 2021 Report Share Posted June 18, 2021 I have done it without taking the crank out of an engine (but not in the car) I think the rear? cap is trickier. But doable. Undo all the caps a smidge, then the top bearings can push round but may require a nudge with a plastic/wood/aluminium/copper "drift" of some description. Doesn't take much. Worth doing all the bearings and the thrusts while you are there, the engine should then be good for many years. Those bearings are not terrible, big ends suffer more. Link to comment Share on other sites More sharing options...
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