Technical Improving reliability

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Technical Improving reliability

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As I work my way through my restoration i'm starting to think about the mechanical aspects.
I'm not overly concerned with additional power, more with the reliability.

With that in mind, what are the common areas that cause breakdowns on these vans and what can be done to improve reliability?
 
Hi
One of the biggest problems is the risk of overheating.
Make sure you have the under trays in place in the engine bay - most of these are rotten now but it's not too difficult to make replacements (albeit with flat steel instead of pressed). I've additionally added some ducting to take heat away from the rad and dump it beyond the bumper, instead of it recirculating up into the engine bay when in standing traffic.

A problem I also used to get (related to the overheating) was vapour lock when refuelling after a long run - sitting at the fuel pump for 30 mins waiting for everything to cool down enough to start again was a pain. I've since replaced the manual fuel pump with an electric one and although I've not been on a long enough run since to properly test the vapour lock issue, what has improved is start up after Connie has been standing for weeks/months (similar problem due to fuel evaporation).

If you look at my thread listing what I've done as part of Connie's restoration you should pick up a few more suggestions.
 
Hi, thanks for the reply
Most of the original ducting is still in place despite the surrounding bodywork being gone.

It sounds like the fuel pump is definitely worth looking into and maybe a couple of heat shields. The main one above the exhaust is missing but should be easy enough to make.

Has anybody played with waterpump pulley size? Just a tweak to up fan speed and pump flow?
 
Hi, thanks for the reply
Most of the original ducting is still in place despite the surrounding bodywork being gone.

It sounds like the fuel pump is definitely worth looking into and maybe a couple of heat shields. The main one above the exhaust is missing but should be easy enough to make.

Has anybody played with waterpump pulley size? Just a tweak to up fan speed and pump flow?
Hi
In theory you could potentially fit a smaller pulley diameter to the water pump & fan to make it spin faster. However, I doubt that in traffic jams the increase in speed would be sufficient enough to make a real difference. More problematic is that at high engine speeds you run the risk of fan cavitation which will make the fan less efficient and could cause additional damage.

As the overheating issue only effects my van after a long run or if stuck in traffic I've added a couple temperature controlled of electric fans. One just in front of the rad (inside the cowling) and the other on the inside of the side vents (rad side). The fans come on at different temperatures (10 degrees different, controlled by the same sensor). The first pulls cool air in from the outside (through the vents) to help the engine bay airflow and if that's not enough the second fan kicks in to force air through the rad. When both are running you don't want to stand behind the ducting unless you want burnt legs.

Note: I've also fit the largest battery I could into the battery space (over double the size of the standard battery) to cope with the extra load. A dashboard light tells me when the fans are running.
 
Yep electric fuel pump and probably electronic ignition.

Use a 145mm pulley from and 850 coupe instead of the 172mm pulley you currently have. They work fine on the 850 coupe upto 6500 revs without cavitation so should be fine on a 900t.

Tim
 
Gary50
I think if I have to go to the extent of adding fans I may look into swapping out the rad and fan/pump assembly and going fully electric on an alloy rad.

Timmycm850
I'll probably look at an alternator upgrade so I'd play with pulley sizes there.
(I can custom turn one on the lathe easy enough.

I have to say that getting one of these to a point of being reliable enough to actually enjoy for even reasonable distances is starting to sound like a lot of time, effort and money.
I have started looking into alternative engines as you can pick up a low mileage panda/500 for around £13-1400.
I've even done some breif investigation into an ev conversion.
 
Ev converting is the answer, loads of room for batteries and no fossil fuel to be ransomed to.
One point to check is your accelerator linkage and it's communication with the engine...
I have just re-commissioned my 900e but was disappointed at it's lack of performance, timing good, carb good, revved fantastic when checking at engine bay but still struggled to see 50mph despite working hard...
Following a lot of headscratching, I got a mate to check the accelerator travel at carb, and lo n behold I was flat to the floor but only getting half throttle at engine end (you can't check both ends at same time by yourself!!!). Simple adjustment got it sorted but what a nuisance after checking all else!
 
I'd love to do an ev conversion. The space under the van makes it a no brainer if money was no object.
Having looked at the various kits, the salvaged evs and cheap second hand cars it looks like the best I could hope for on a £5k budget would be an 80 mile range on a 10 hour charge.

Thats fine if you just want to potter around the local shows but I'd hoped to venture a little further than that.
 
I am still keen to explore engine swaps. The main problem seems to be finding an engine with correct rotation. I have now discovered pre 2000 Honda's rotate ccw. A small mod to rear bulkhead, modify rear crossmember, adapter plate for fiat bellhousing and mess with clutch a bit? Could 16valve efficiency really be that simple and has no one tried this route? I understand there are other issues, but if a full honda donor car is available then the electronics etc can be grafted too?
 
Extra strong springs due to the extra weight on the rear, stronger shocks due to the extra spring rate.

Front radiator and plumbing to suit,

Transverse engine mount?. Longer final drive otherwise your still doing 6k revs at 65mph. Complete fuel system change as you have fuel injection to deal with.

Might be too high an engine under the rear parcel shelf.

Food for thought.

Alternatively get an 899cc from a cinquecento and bore it to 965cc and use a larger punto 1.1 throttle body to feed the 965cc with fuel mix. 850 saloon gearbox. More reliability and 55hp reliably using fuel injection SPI.

Tim
 
I'd have thought the weak link in that chain would be the gearbox and driveshafts.

I think for any meaningful gains you'll be better off changing to a vw box and using a modern fire 1.1 or 1.2 engine.

Low mileage pandas can be had for very little money these days.
 
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