GM 350 small-block starter motor nightmare!
Discussion
Hi Guys.
Just bought an overfinch discovery with 350 chevy small block.
Was wondering if anyone was aware of the starter-motor fitment issues.
It turned out that when I collected the car the starter had meshed to the ring gear and I drove it 150 miles without realising - stopped for fuel and it wouldn't start again as the starter had been spinning constantly and had burnt itself out - found myself still 300 miles from home(outside glasgow) and left the car at a garage there and got the train home(couldn't bump-start as auto). RAC wouldn't help as I had already had the car looked at.
Eventually found a starter and had it delivered - it needed a 10mm shim fabricating to bring the starter arm far enough back that it didn't mesh again - but then the bolts were too short - another nightmare finding longer bolts.
It appears that overfinch had been aware of this as a notch was cut out of the bellhousing to assist in judging the fitment.
Is this a common problem? Is anyone aware of any other well-known issues I should be aware of.
I would be grateful for any tips/info.
N.B. The running gear from this discovery is going into my defender 90 (currently with TVR V8).
Thanks in advance
Victor
Just bought an overfinch discovery with 350 chevy small block.
Was wondering if anyone was aware of the starter-motor fitment issues.
It turned out that when I collected the car the starter had meshed to the ring gear and I drove it 150 miles without realising - stopped for fuel and it wouldn't start again as the starter had been spinning constantly and had burnt itself out - found myself still 300 miles from home(outside glasgow) and left the car at a garage there and got the train home(couldn't bump-start as auto). RAC wouldn't help as I had already had the car looked at.
Eventually found a starter and had it delivered - it needed a 10mm shim fabricating to bring the starter arm far enough back that it didn't mesh again - but then the bolts were too short - another nightmare finding longer bolts.
It appears that overfinch had been aware of this as a notch was cut out of the bellhousing to assist in judging the fitment.
Is this a common problem? Is anyone aware of any other well-known issues I should be aware of.
I would be grateful for any tips/info.
N.B. The running gear from this discovery is going into my defender 90 (currently with TVR V8).
Thanks in advance
Victor
As far as I know you are supposed to shim starter motors on small block Chevy's, but only small thin shims not 10mm.
Not sure what engine came in different Overfinch RR's but I know older gen one blocks (pre-93') had 2 different size flywheels too, not sure about newer ones, and not sure what gearbox they use either which also may change things..
You can get high torque mini starters too, which are a better design and much easier too fit, and in my personal experience on my car needed no shims either.. !!
Not sure what engine came in different Overfinch RR's but I know older gen one blocks (pre-93') had 2 different size flywheels too, not sure about newer ones, and not sure what gearbox they use either which also may change things..
You can get high torque mini starters too, which are a better design and much easier too fit, and in my personal experience on my car needed no shims either.. !!
Sounds a bit strange... SBC starters mount to the block and are independent of the gearbox used. The only variable is the flywheel (152T vs 168T). There are a couple of mounting positions available with most mini-starters to accommodate either flywheel. If using a stock-type starter, you'll need the correct one to mate with the appopriate size flywheel... this might be your problem.
Regarding shimming, the idea is to use thin metal starter shims to obtain the proper clearance between the starter bendix and the ring gear in terms of engagement depth. With mini starters, they're designed to engage only approx. 50% onto the ring gear in the fore-aft direction.
Regarding shimming, the idea is to use thin metal starter shims to obtain the proper clearance between the starter bendix and the ring gear in terms of engagement depth. With mini starters, they're designed to engage only approx. 50% onto the ring gear in the fore-aft direction.
Hi Ian,
thanks for your advice - I have become aware of all of this over the past couple of weeks, however, fact is it still needed a 10mm shim - probably to do with the fact that I have a beefed-up ZF 4-speed gearbox(Landrover) with a huge torque converter with a custon bellhousing - rather than a chevy one.
I have a feeling overfinch made a hybrid flywheel to mate the chevy block to the the ZF gearbox, which could be the cause of the problem.
However, Overfinch went bust a couple of years ago and the new owners have no records of any build data before 2003.
thanks for your advice - I have become aware of all of this over the past couple of weeks, however, fact is it still needed a 10mm shim - probably to do with the fact that I have a beefed-up ZF 4-speed gearbox(Landrover) with a huge torque converter with a custon bellhousing - rather than a chevy one.
I have a feeling overfinch made a hybrid flywheel to mate the chevy block to the the ZF gearbox, which could be the cause of the problem.
However, Overfinch went bust a couple of years ago and the new owners have no records of any build data before 2003.
vjj said:
I have a feeling overfinch made a hybrid flywheel to mate the chevy block to the the ZF gearbox, which could be the cause of the problem.
However, Overfinch went bust a couple of years ago and the new owners have no records of any build data before 2003.
Nail and head in above first line, as Ian said, starter bolts to block so cannot be the problem with stock ring gears/flexplates so must be a custom ring gear/flexplate.However, Overfinch went bust a couple of years ago and the new owners have no records of any build data before 2003.
Even before they went bust Overfinch where not interested in their past and were unhelpful at best. Are you sure its an Overfinch ? as I have seen it discussed before Re. an 'Overfinch' Disco for sale on ebay that they never made any, several Chevy Discos for sale have been described as being converted "as Overfinch would have done" had they built any.
Definitely an Overfinch
Have the conversion invoice. Done in 1995 when car was new
Upgrades as follows
Chassis waxoyled
Overfinch level 2 conversion - engine (GM350 LT31 Vortec - 275bhp, 340lbs torque), suspension, brakes, steering rack,sports headers, stainless exhaust system, Rear wheel cover, steering wheel badge.
At the time it had injection but now has a big Holley and Offenhauser inlet.
Apart from that there is a plaque in the engine bay with the engineer's name on it.
There is one other for sale on Ebay by a Range Rover specialist in Oxfordshire for 25 Grand
I have very recently spoken to him and it turns out he was part of the Overfinch setup in the golden years of the nineties and he remebers my car - he says they built a handful(four or five) including one which was 300tdi!
His car is much earlier,1991 and has a manual box and all the interior stuff like recaro seats and red instruments.
Anyway, here is my plan - as they left the ECU in the discovery I will put an normal 4.0 Rover V8 and standard gearbox into it and sell it on - its in very good nick.
The 350 lump, adaptors, steering rack, etc, and the beefed-up gearbox are coming out and going into my defender, replacing the TVR 4.3 and 3-speed Torque-flite currently installed. I am also fitting a new chassis at the same time.
I am replacing the cast iron heads with new high-performance aluminium items and putting in a high-torque camshaft - should make about 320 bhp and 400lbs/ft torque. Factor in my Defender is a convertible and with the chevy installed weighs only 1400kgs and I should have a fast little truck - as she is a 1984 the are no cats to worry about so I will be having the mother of all exhausts.
Thanks again for all the info and help
Have the conversion invoice. Done in 1995 when car was new
Upgrades as follows
Chassis waxoyled
Overfinch level 2 conversion - engine (GM350 LT31 Vortec - 275bhp, 340lbs torque), suspension, brakes, steering rack,sports headers, stainless exhaust system, Rear wheel cover, steering wheel badge.
At the time it had injection but now has a big Holley and Offenhauser inlet.
Apart from that there is a plaque in the engine bay with the engineer's name on it.
There is one other for sale on Ebay by a Range Rover specialist in Oxfordshire for 25 Grand
I have very recently spoken to him and it turns out he was part of the Overfinch setup in the golden years of the nineties and he remebers my car - he says they built a handful(four or five) including one which was 300tdi!
His car is much earlier,1991 and has a manual box and all the interior stuff like recaro seats and red instruments.
Anyway, here is my plan - as they left the ECU in the discovery I will put an normal 4.0 Rover V8 and standard gearbox into it and sell it on - its in very good nick.
The 350 lump, adaptors, steering rack, etc, and the beefed-up gearbox are coming out and going into my defender, replacing the TVR 4.3 and 3-speed Torque-flite currently installed. I am also fitting a new chassis at the same time.
I am replacing the cast iron heads with new high-performance aluminium items and putting in a high-torque camshaft - should make about 320 bhp and 400lbs/ft torque. Factor in my Defender is a convertible and with the chevy installed weighs only 1400kgs and I should have a fast little truck - as she is a 1984 the are no cats to worry about so I will be having the mother of all exhausts.
Thanks again for all the info and help
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