Pdv Posted October 6, 2022 Report Share Posted October 6, 2022 Hi, I have just bought a 1500 MG engine and gearbox. Has anybody fitted one to a Herald please and any tips help would be most appreciated. The gearbox came without a gearlever, does the Herald one fit?. Will give it a good clean and then find any identification to help with any parts needed, looks like sump gasket set for example. Thanks Steve Link to comment Share on other sites More sharing options...
Pete Lewis Posted October 6, 2022 Report Share Posted October 6, 2022 if the mg midget 1500 used the same as triumph with a single rail gearbox the gearstick is not an easy find. Pete Link to comment Share on other sites More sharing options...
Josef Posted October 6, 2022 Report Share Posted October 6, 2022 Pretty sure the gearbox is the single rail one as fitted to Spitfires. In which case finding a three rail one to fit with the 1500 engine would be easier as the single rail gearbox is longer. And no the gear-levers are not interchangeable between three rail and single rail boxes. Link to comment Share on other sites More sharing options...
johny Posted October 6, 2022 Report Share Posted October 6, 2022 Then a new 10 spline clutch plate will be required as well.... Link to comment Share on other sites More sharing options...
johny Posted October 6, 2022 Report Share Posted October 6, 2022 Worth trying the new gearbox as its only an inch so an original prop with sliding joint might fit? Link to comment Share on other sites More sharing options...
NonMember Posted October 6, 2022 Report Share Posted October 6, 2022 1 hour ago, johny said: an original prop with sliding joint Not many Heralds had the sliding joint - that was a Vitesse/Spitfire/GT6 thing. Link to comment Share on other sites More sharing options...
Pdv Posted October 7, 2022 Author Report Share Posted October 7, 2022 Hi, Thanks for the replies, the engine and gearbox are complete so no problems with the splines, but was going to separate it to check if the clutch is ok. Was surprised that the gearlever was not present will contact the seller, if not Mathew I will be in touch.if that is OK. Thanks Steve Link to comment Share on other sites More sharing options...
johny Posted October 7, 2022 Report Share Posted October 7, 2022 No the splines only become a problem if you change the gearbox because the new one you have is 1" longer than the old so your existing propshaft maybe too long. Good idea to check the clutch and then when unit installed drive it a bit with the gearbox cover off to confirm all ok👍 Link to comment Share on other sites More sharing options...
DanMi Posted October 7, 2022 Report Share Posted October 7, 2022 you will also need to consider the speedo as that will be out if using the single rail gearbox. Plus I would consider gearing, as the 1500 engine is a more torquey lower revving unit than the 1300/1147. I had a 1500 in my MK2 spit (also 4.11 diff) and it was under geared but ok as I have overdrive. maybe swop to a 3.63 from a spit 1500? Link to comment Share on other sites More sharing options...
DanMi Posted October 7, 2022 Report Share Posted October 7, 2022 If you decide to stick with the herald gearbox (speedo will be fine and no custom propshaft) then you can use the herald clutch and flywheel, though you would have to drill the flywheel bolt holes to take the larger 7/16 ? bolts, this is what I did with my spit. 1 Link to comment Share on other sites More sharing options...
NonMember Posted October 7, 2022 Report Share Posted October 7, 2022 11 minutes ago, DanMi said: maybe swop to a 3.63 from a spit 1500? Definitely swap the diff. We put a 1500 into a Herald with a 4.11 and it was... good for a laugh. The 3.63 diff transformed it. 3 minutes ago, DanMi said: you can use the herald clutch and flywheel, though you would have to drill the flywheel bolt holes to take the larger 7/16 ? bolts, this is what I did with my spit. That's what we did, and I've now got that engine/flywheel with a Mk4 box in my Spitfire. Link to comment Share on other sites More sharing options...
Clive Posted October 7, 2022 Report Share Posted October 7, 2022 If you use the single rail box, a vitesse non od (or big saloon) propshaft will fit However, the herald uses small flanges on the gearbox and diff, single rail is big flange. A swap to 3.63 diff would sort that, but the driveshafts have the same issue. The very late 4.11 diffs are handy as you can swap the quarter shafts with the 3.63 fixing that issue. As you have noted, you need to swap the sump (I think) but any hearald/spit sump gasket will fit. It will also give you teh chang-ce to easily inspect the crank bearings, do not pass up the opportunity. I like a 1500 herald. I have had a few, but I have always kept the 4.11 and used overdrive. Makes a very quick little car, still cruise at 70+ all day. Link to comment Share on other sites More sharing options...
DanMi Posted October 7, 2022 Report Share Posted October 7, 2022 17 minutes ago, clive said: The very late 4.11 diffs are handy as you can swap the quarter shafts with the 3.63 fixing that issue or you change the flange on the halfshaft/propshaft Link to comment Share on other sites More sharing options...
Clive Posted October 7, 2022 Report Share Posted October 7, 2022 14 minutes ago, DanMi said: or you change the flange on the halfshaft/propshaft Very true, but changing a prop flange will probably put it out of balance, and swapping a quarter shaft takes a few minutes. Link to comment Share on other sites More sharing options...
johny Posted October 7, 2022 Report Share Posted October 7, 2022 And I bet Steve thought this swop was going to be straight forward😭 Link to comment Share on other sites More sharing options...
Clive Posted October 7, 2022 Report Share Posted October 7, 2022 5 minutes ago, johny said: And I bet Steve thought this swop was going to be straight forward😭 That is my concern. Easiest is to use the existing gearbox, and using a morris minor clutch plate (I think) nd see how it goes. In fact, it will go very well, but run out of revs at 70. Link to comment Share on other sites More sharing options...
johny Posted October 7, 2022 Report Share Posted October 7, 2022 Clutch is easy as Rimmers list a 10 spline 7.25" friction plate GCP103 for non UK 1500 Spitfire (apparently some of these had a 3 rail box)... Link to comment Share on other sites More sharing options...
NonMember Posted October 7, 2022 Report Share Posted October 7, 2022 11 minutes ago, johny said: Clutch is easy as Rimmers list a 10 spline 7.25" friction plate GCP103 for non UK 1500 Spitfire (apparently some of these had a 3 rail box)... Yes, 1974 US model, using the same clutch as a 1500TC. It may well also be the same as a Morris. Link to comment Share on other sites More sharing options...
johny Posted October 7, 2022 Report Share Posted October 7, 2022 8 minutes ago, NonMember said: Yes, 1974 US model, using the same clutch as a 1500TC. It may well also be the same as a Morris. Do you know if the Herald clutch hydraulics and thrust bearing will all be ok for it then? Link to comment Share on other sites More sharing options...
DanMi Posted October 7, 2022 Report Share Posted October 7, 2022 so long as it is the diaphragm clutch (ie Herald post about 1965) the the hydraulics and thrust are the same. As I have said, you can use the existing herald clutch and flywheel on the 1500 engine with a 3 rail gearbox. Link to comment Share on other sites More sharing options...
johny Posted October 7, 2022 Report Share Posted October 7, 2022 No what looks better is to keep the flywheel and bigger clutch of the 1500 but with new 10 spline 7.25" friction plate (GCP103) and then as you say all hydraulics and thrust stay the same. The first gear ratio of the Herald 3 rail box however is quite a bit lower than that used in the Spitfire 1500 so for it to remain useable changing the diff becomes even more important.... Link to comment Share on other sites More sharing options...
Pdv Posted October 7, 2022 Author Report Share Posted October 7, 2022 Hi All, Well yes it did seem easy at the time. So where to start, I purchased this as a complete unit ie straight out of a car, so in theory it can, apart from a few things to change it should be relatively straightforward. I initially asked for a Spitfire 1500 engine and gearbox, the person I bought this from is well known and has been trading for years and he said what I have got is a very good MG engine and gearbox with no mention of any issues flitting it. OK so I think I have a 1500 spitfire engine as fitted to MG Midgets with a Morris gearbox, I was told that a 13/60 manifold will fit and I purchased a stainless exhaust as well. I will need to change the flange on the gearbox as it is to big as has been said, the engine mounts are different but i have some and had a look and I think they will fit, they are smaller so not sure they are OK for a heavier load. I have a shorter prop if that is required. Thanks for all the replies. Steve Link to comment Share on other sites More sharing options...
johny Posted October 7, 2022 Report Share Posted October 7, 2022 Pretty certain the engine and gearbox are the same for 1500 Spitfire and Midget. I think perhaps you should install it with a prop thats shorter, if required, and has the rear flange changed to match your existing diff. You can then drive it and decide later if you want to change the diff for another ratio.... Link to comment Share on other sites More sharing options...
Peter Truman Posted October 7, 2022 Report Share Posted October 7, 2022 I have the same ie Midget 1500 with single rail gearbox, which has been modified to a 3 rail with J Type O/D, the engine has been rebuilt and awaits fitting in a Spitfire, maybe! The only difference I found with the gearbox was the rear mounting where a cross bar is fitted into the mounting to limit the gearbox's rotation I assume as the midget's gearbox is mounted in a tunnel & could when accelerating rotate enough to hit the close confines of the tunnel. Link to comment Share on other sites More sharing options...
DanMi Posted October 8, 2022 Report Share Posted October 8, 2022 If you have the shorter prop then it is pretty straight forward. 1360 exhaust manifold is fine, the engine mounts for all 4 cylinder small chassis Triumphs are the same so no issue there. The sump I believe will need swopping and if you use the 1300 one it may need bashing to clear the front crank big end 1500 has a "lump". The only other issue will be getting the speedo accurate, cars with 3 rail boxes changed the ratio by using differently calibrated speedos the single rail had different drive gears to give 100 turns per mile. 1 Link to comment Share on other sites More sharing options...
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