Spring Valley Bus meets Corvair

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A bit of an update, I started to have fan belt issues having just rectified a long term clutch/oil leak problem, that turned out to be caused by a worn/damaged pilot bush. The belt shredded on the way home, managed to get around a mile away from the house when the gen light came on. Luckily I was able to pull into a car park and replace the belt. When I got home I noticed the new belt had worn badly already, something not quite right here!

I used the van a week later and the belt flipped off after about a mile, I’ve never had an issue with the belt before and bearing in mind the journey the belt takes on the corvair engine it can be an issue for some. I fitted a new belt by the side of the road (again) and off I went. Now an indication then something isn’t right is when my volt meter drops to 12v rather than the 15v (ish) that it normally sits at, so after a few miles I pulled off a side road and noticed the volts drop, jumped out and to take a look and it was apparent that the belt had twisted, this was enough to strop the alt charging. So loosened the pulley, untwisted the belt and went on again, this happens pretty much every time I went from cruising speed to stop ie junction or roundabout. Slightly peeved I went home!

So today I thought I best investigate, so stripped off the tinwear and inspected the fan and the pulley, both span freely, but the alternator seemed like it was catching slightly, problem identified! Took the alt off to see what was up, nothing! For some reason it span perfectly well off the engine, weird! Anyway, everything bolted back together and just back from a run, everything smooth and how it should be! At least now I know that if it happens again where to look.

Off to Bristol Volksfest next weekend, hope to see some of you there ✅
Bought a new alternator, had to strip it apart to use the Corvair mount but was pretty straightforward


Just back from Camperjam and it ran like a dream

Glad the engine is now running well. So was the problem the alternator bearings in the end then?
I’m not 100% sure, it spun fine off the engine. It blew a diode on the way back from camper jam about 3 years ago, I had it repaired but it has never been right since, giving out 15v but I lived with it until it started throwing belts. Bearing has to be suspect but it feels smooth without any movement…
I know your engine is a Corvair, but I had some alternator problems as well. The belt kept coming loose. I thought it may be the alternator bearings but since replacing the pulley wheel all seems well now.
I know your engine is a Corvair, but I had some alternator problems as well. The belt kept coming loose. I thought it may be the alternator bearings but since replacing the pulley wheel all seems well now.
Weird how a pulley wheel can slacken a belt. Annoying when these happen tho!
Hi all. Nice to see people still using this place. It’s getting close to that time of year again when the van comes out to play and this year all mechanicals are behaving themselves thus far! After leaving the van for a few weeks it’s been increasingly difficult to start so time for a new battery!


Or I was thinking of ditching the Chevy for these two batteries and a motor….


Obligatory rear end pic with new sticker added #egotrip
In September 1981, near Lake Henshaw, in southern California, I came across an abandoned Chevrolet Corvair which still had its rear-mounted, six-cylinder air-cooled engine. Sadly, I didn't have my tool kit with me and there wasn't enough spare room in my suitcase to take it home on the flight from Los Angeles to London. I wonder what HM Customs would have said if I had!?!

The downward-facing cooling-fan and drive-belt with idler pulleys seemed rather strange then, but I have since seen a similar after-market configuration, for use with VW Type 4 style air-cooled engines.

There's a whole chapter about Chevrolet Corvair engines in Bill Fisher's book about "hot-rodding" VW air-cooled engines (all types!?!), which strangely omits any mention of VW Type 4 style air-cooled engines, despite its 1970 publication date.

Bill Fisher, "How To Hot Rod Volkswagen Engines", HP Books, 1970, ISBN 0-912656-03-4
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The flat six 110 version of this engine suits a Type2 bus so well, it's a shame there are not more about. One maybe two others in the UK I Think but both running the Powerglide 3sp Auto box whereas mine is a manual, now on a 3rib box with better gearing. I fitted it about 5 years ago and still haven't needed to adjust the tappets in that time! The only issue I have had is a leaking RMS and a damaged Pilot bush resulting in gearbox oil being thrown onto the clutch. Both took a while to diagnose annoyingly, mainly due to my lack of experience with this engine. I am still not convinced this alternator is going to be any better than the last that failed within a short space of time but thats another story!!
Pulled the bus out the other week and surprise surprise the alternator wasn't producing a voltage again! That's two now that have failed within a short time span, and i mean like 200 miles or so! This is an Si10 type from ebay, I have to take the front housing and swap it for the corvair to mount the damn thing thus voiding the warranty! The alternative is to ship one from the states but the cost is ridiculous, however at this rate it might have been the cheaper option!

So today I've sent the alt off for inspection to see if I can find what's caused the last one to fail so quickly, on inspection there is no sign of damage to the diode or regulator, everything looks like new as you would expect, hopefully if nothing else I'll have a working spare as I don't expect this latest one to last any longer as its only kicking out 13.55v :mad:

Just in case anyone else is having issues, the Corvair engine is a '65 110 that originally had an alt with an external voltage regulator, i have checked and double checked the wiring is correct. One terminal is for the dash warning lamp and the other is a switched live from the ignition, fairly simple affair so i'm assuming the issue lies with the quality of the parts in the alternator.....
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Can you get the alternator youve bought from eBay rebuilt at a local old school engineering place to a better quality?
Can you get the alternator youve bought from eBay rebuilt at a local old school engineering place to a better quality?
That’s exactly where it currently is.

Went away for a few days and the new alt didn’t start to charge for a few miles into the journey, I then got between 13-15v at random speeds throughout the trip, this was A-Roads rather than a constant rev/speed on a motorway trip. I mean I can live with this but experience tells me that it will quite possibly not charge at all on the next trip.

I’ve had a previous alt repaired without a positive result. Making me think the issue lies elsewhere, but this is unlikely as the wiring is simple and checks out correct
Ok so might have found my alternator issue, I stumbled across this drawing and it shows that pin 2 cable must have a cross section of 2.5mm2 or larger, now my cable here was part of the VW loom and is around 0.75mm2 and comes from the ignition switch.


So I ran a 6.0mm2 cable from pin 2 direct to the battery, leaving off the original VW loom wire.


The result is a clear 14.4v on the gauge


I have a couple of days off now so will test this *fingers crossed*
So being happy that the alt worked didn’t last long. Noticed that it wasn’t charging and that the gen light increased in brightness with revs (that’s a new one on me) when I started it this week. Decided to take it to the local auto electrician who incidentally have my old unit for testing.

On the bench it produced a voltage fine so I discussed a few ideas with them about wiring etc. unfortunately their knowledge of this alt was less than mine so after more research I’m convinced I have it installed correctly. Bolted it back on and it’s working fine chucking out 14.4v on the meter.

Went for a drive this afternoon, multiple journeys, lots of engine starts and a mix of A,B & motorway and it never missed a beat. Even had the headlights and wipers on with only a small deflection in voltage.

So in conclusion, I think these alternators are belt tension sensitive, I made a point of getting the belt as tight as I could when installing it this time around and that seems to be the key. There is a lot of info about these engines flipping fan belts due to the angle of travel but in fairness I’ve never experienced this.

Here’s to a happy summer in the van 🙏
Done a few miles lately and what with the alternator issues seemingly behind me I turned my attention to the annoying squeaky near side front brake. I had forgotten that I’d actually changed the front calipers a few years ago as that was the job I was going to attempt this evening as I stumbled upon a pair the other day in the garage.

I took the pads out and inspected, added some copper slip to the backing plates then noticed some play in the hub. I took the cap off and the grease was black and didn’t look good, so checked the bearing and a needle roller fell out, meaning that the race was damaged. Luckily I found a spare in the garage and put it all back together.


Just took it for a drive but there is still an annoying speed related noise that I can’t pinpoint.

However, on reversing, the bus has been juddering whilst slipping the clutch of late, speaking with Nick (CJ Motors) this weekend he suggested I check the engine mounts so I did


A clear crack! So I’m hoping that this will solve both issues

So changed the snapped engine mount but i still have a reverse judder. The other mount is in good condition, I would have liked to change them as a pair but JK only had one and I'm off this weekend in the bus so couldn't wait. The 3rib transmission does have the 6rib bell housing with the fixing bracket modified to bolt to the chassis so will check that at some point too.

I experienced a grinding noise coming from the near side rear brake area on the way home this weekend, it was speed related but not brake dependant, On the plus side this turned out to be a loose rear hub nut, split pin was present and doing it's job! Now all sorted!
Just back from Cornwall and according to the odometer did over 700 miles of trouble free motoring (actual fact it was around 550miles!)

Alternator produced a voltage and it was nice leaving the fridge on all day whilst we were out discovering knowing it would charge on the way back to camp!

A couple of issues now to sort, nearside brake is binding slightly, thought I sorted this with the bearing and it did for around 10 days before it appeared again so just bought a full front wheel bearing set to see it that sorts it which i imagine it will.

Next up the judder in reverse. This was a ballache i won't lie! I need to get it on a ramp to check all the mounts (I have an 091 bellhousing bolted to the chassis with a 090 'box) and make sure the engine bar etc is undamaged before i look at the gearbox itself.

4th gear popping out: Might be related to the above and will decide what to do when inspected all the joints and fixings including the selector.

Other than that is starts/stops and goes well. Driving home against 50+mph winds was no fun I can tell you but considering we were fully loaded, 5 up with a binding brake in those headwinds i managed 23mpg with a 2.7l motor

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