- This topic has 13 replies, 6 voices, and was last updated 11 years, 1 month ago by
.
-
Posts
-
I purchased my Allison MGTD this summer and when i got it realized the previous owner had put some bumpers under the engine cover. The alternator wheel had rubbed a small hole in the engine cover (luckily its hidden under the spare tire). I just replaced that alternator and now i have ever more rubbing. I can easily fix this by adding a larger bumpers and the result is that the engine cover has about a 1 inch gap. This isnt killing me as im not into the pristine condition vehicles anyway. But it makes me wonder what the problem is.
1- the original fit was off. (thats unlikely as i understand that Allisons were really well done and they were factory made so this seems like something they would have dealt with)
2-the alternator is slightly larger than the original that came with the car. (the alternator i had was a Motorola and i replaced with it with the same model but Napa brand. Neither of these are the actual 1967 external that probably came with it, but even so they should stick out much further of the belt wouldn’t fit right… right?3- engine sits different than original (this is a total wild guess and i don’t even know if its logical. Can the engine be mounted differently than the original? meaning can it be moved toward the rear of the car an inch or so? )any help you can provide is greatly appreciated.My guess, and this is just a guess, is that whoever converted from the stock generator to the alternator took some short cut and that caused the problem. Post some pictures.
How does the belt tighten on the alternator? If it’s not like the generator’s pulley-squeeze method I might have a theory.
My theory is similar to Roy’s.
Car built with a generator. A previous owner converted to alternator, realized he/she did not have clearance and added the rubber bumpers to lift the engine cover.
I am interested in Ed’s theory tho! 😉
As far as your engine mounting question, no. Not possible. VW engine mount is straight forward. Lift it up, slide it in and bolt it to the transaxle. I don’t see how it could have been modified.
Paul Mossberg
Former Owner of a 1981 Classic Roadsters Ltd. Duchess (VW)
2005 Intermeccanica RoadsterIf you own a TDr and are not in the Registry, please go to https://tdreplica.com/forums/topic/mg-td-replica-registry/ and register (you need to copy and paste the link)
Yeah, I got nothing.
All I’ve read says the alternator stand is shorter than the generator stand. And alts are as a rule quite a bit shorter than generators (though the pulley has to still be out there even with the crank pulley, so that shouldn’t matter). What I was wondering–since I’ve never looked at one close up–was whether an alt-equipped Beetle would also have a “slide-lock” links of belt adjustment like pretty much every other car on the road has. That, and a too-long belt, could get the alt fan up high enough to do some damage, I thought.But of course that makes no sense since the engine cooling fan still needs to be driven…It never before had occurred to me that going to an alternator could cause clearance problems under our bonnets.edsnova2013-11-10 22:10:46
Ah, and now I see it. The bloody things are huge. This one also has some kind of bullet-shaped nut holing the pulley on. So it might be that…
The alternator stand and the generator stand are different. That’s due to the wider portion of the alternator. While a generator will fit on an alternator stand the reverse is not true. I don’t think one is taller than the other but I’m pretty certain the alignment of the fan belt from the crank pulley to the alternator/generator pulley is the same.
Allen Caron
VW based 53MGTD - "MoneyPenny"
"If one thing matters, everything matters" - from the book The ShackAgree with Alan. Also, remember that the original VW engines with alternators were all with dog-house cooling shrouds that used different, thicker fans.
I don’t have any experience with them, nor with all the aftermarket ones available today, so I’m reluctant to offer any opinions…Early FF TDr on 69 VW pan
Slowly coming back from the ashes...Mike,
I think it’s time for some pictures of the engine bay and cover.Paul Mossberg
Former Owner of a 1981 Classic Roadsters Ltd. Duchess (VW)
2005 Intermeccanica RoadsterIf you own a TDr and are not in the Registry, please go to https://tdreplica.com/forums/topic/mg-td-replica-registry/ and register (you need to copy and paste the link)
thanks for input. I took some pictures so you could see what i have as opposed to what you might have. Keep in mind i have never even looked at a VW before this one so i don’t know what looks normal and what does not. When i ordered the 1st replacement alternator i got one for a 1967 engine. But the one that they gave me was what i assume is a standard 67 alt. But the one that i had in the car was a Motorola. The problem i had was that the Motorola had an external regulator attached at the top so i wanted to stay close to same thing. i eventually ended up with the same physical model but the regulator was internal. Its a AL82N if you want to look it up. But here are the pics.
alternator
just to give you a sense of scale..you probably dont need this, but it seemed like a good idea at the time
The white spot is the grove its cut. Again there was an initial groove that was rubber through. I have now added a slightly different groove in the same spot.
The cylinder head tins are there Ed. That’s all I run…but let’s resurrect the engine cooling thread for discussion.
Back to Mike’s alternator…
Mike,
First, I’m sure you know this, but there is technically no such thing as a “standard 67 alternator.”
Standard is a generator. Later model Beetles had alternators…I think beginning in 1973.There is obviously no way to tell how your Allison was equipped when it was first built. But I’d be willing to bet it had a generator, and an owner somewhere along the line swapped it out for an alternator.
The alternator has a larger diameter than a generator, hence the need for the shorter stand, to keep the axle aligned with the fan. But…that still leaves the top of the alternator higher than the top of the generator. And there-in lies the rub…literally in this case.
I doubt it’s the pulley hitting the engine cover. I suspect it’s the body of the alternator itself. The natural vibration of the engine, and the body is creating the wear spot.
Since it’s under the spare tire, I suggest you just clearance the engine cover a bit more where the rub marks are.
Paul Mossberg
Former Owner of a 1981 Classic Roadsters Ltd. Duchess (VW)
2005 Intermeccanica RoadsterIf you own a TDr and are not in the Registry, please go to https://tdreplica.com/forums/topic/mg-td-replica-registry/ and register (you need to copy and paste the link)
Looks like from the wear marks that it might be that bit sticking out at about 3 o’clock on the alternator.
Guys thanks so much for the input. I am going to just add some bumper spacers to the engine cover and let that be the simple fix. Its not the best but I don’t treat the car as a show car so a few imperfections aren’t going to kill me. Its simpler than sourcing a new alternator or going back to a generator simply for space. I’m still having some rubbing issues with the fan but that’s a different post. Again thanks for the help.
- You must be logged in to reply to this topic.