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Discussion Starter · #1 ·
another saga... rebuilding a 1.6 early engine , totally pissed off with the dense smoke that greeted anyone around me when i started her up after a total rebuild, all except the engine.280k. i got a gift of an early engine, a spare from an ex race guy, for 30 quid it had been a UK car rusted out, he'd kept the engine and sold everything else over the years reckoned from memory it had around 70 k.. equipped i pulled the head and sent it away to a local engineer to get rebuild std, light skim oil seals and guide sleeved. 14 days later returned and we installed it on my old engine that was in the car, still had start up white grey smoke, so my friend a bloody good and steady no nonsense experienced car guy says will fetch me up that short motor, so i can see inside these units, it has to be oil rings, i did and he found 4 seized oil rings on the pistons,all the brgs had been replaced and everything else miked up std and in vgc, so he reckoned mine in the car could well be the same.. ok we start a rebuild on the short motor, removed the engine and box cause the gearbox fine for a few weeks after the auto conversion,leakedoil steadily until it got noisy and harsh, i had another, so my mechanic says after examining the propshaft that one you had fitted is about 50mm too short.. my query is i know that the auto one is shorter, the 2 i have.. a mk1 std and a mk2 std are the same length, so why are we finding a 2 inch discrepancy in shaft length.. i know theres a few mm in the PPH for adjustment but why 50mm..anyone know???
 

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Happily expanding the To Do list since 1997
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I don't know about autos but I do know the shafts for the manual '89-'93 1.6 are a different length from the manual '93-'05 1.8 cars (and the later '95-onward 1.6 cars too) because the early 1.6's have a smaller diff. If your Mk.1 prop is the same length as your Mk.2 prop then it's the revised 1.8 size to fit a 7" ring gear diff and not the early 1.6 size which goes with a 6" ring gear diff.
 

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Discussion Starter · #3 · (Edited)
OK how is it then that most ''experts'' will say that its easy to change a diff in any mk1 to a 7'' slip diff from a 2 just take everything diff shafts and uprights i haven't yet read mention of a prop shaft issue which is what youre saying, i'm friendly with the largest breaker over here,Ulster, i went to get a mk1 prop a few weeks back he had maybe 60 1's and 2's in a row, on their ends they're all similar size just that early mk1 have a different diff end spider size pcd and actual spider end diameter size as well..
 

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Happily expanding the To Do list since 1997
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It's always been my understanding that the early cars need both the axles and the prop shaft from a later car to match the later diff. It may be that I misunderstood the nature of the difference in the prop shafts and just assumed it was their length. If indeed it is only the fittings that don't match and not the length then sorry for giving duff info.

(Edit to add) I see Autolink list both the early and later types of propshaft on their website and they say each one is suitable for both auto and manual cars. The mystery deepens.
 

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Discussion Starter · #5 ·
Really its just me being a real car nerd perhaps and asking 'why' all the time.. i have always been accused when telling a story about getting all the detail correct,makes sense in my mind to have the whole picture example when i was doing research of the auto to manual swop , everyone wrote autos never have a slip, my eunos did yet i never noticed it driving when auto, but i bloody did one night just after she went manual, and no one mentioned that the auto prop would be too short or too long and that included the PPF so i got a mk2 shaft and MK1 PPF discovered it wouldn't bolt up to the diff see back messages, these guys who do write ups on line are great but tell the whole story chaps it bloody matters when youre faced with more searching more expense and more headaches.. this isn't a big issue as my wizard can machine us a suitable measured up spacer , [the local prop fettler says leave 18mm for plunge] and has stronger longer bolts to fit it ... he does a lot of truck repairs, chassis fettling and recovery tilt and slide changes...W
 

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Discussion Starter · #6 ·
the issue has become clearer at long last.. yes the mk1.6 prop as long as it had the original 6inch basic slip or open diff is 42inches long whereas the mk2 with the later diff has a different diff end bell where the diff and prop meet and has a 39.37'' 1 metre shaft... and slightly different end plate, bolt hole size and pcd wise, smaller than a mk1..
 
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