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Re: ongoing re commission of our RX7

Posted: Mon Jul 24, 2023 11:49 am
by rustyrescue
I will keep our updates running on this thread unless mods think it is time to start afresh?

Daughter and I took "Humphrey" for its longest run yet....and had a cracking day at Simply Japanese. About 180 miles. It also went out last week for a "pro Photo shoot" with a friend of daughter one who has a soft spot for them and offered to do it for his own portfolio....he does cars cars cars. We await the outcome with great excitement.

The car runs lovely, the carb issues I hope are behind us after a further play recently. I can take the top off blindfold :D

We have three issues remaining before we turn to any simply cosmetic improvements.

1) Still runs a bit warm if loaded up a hill or in traffic for too long. Mostly holds just under or on half gauge but creeps up a bit. I have some thoughts, but usual checked, timing etc. Flushed out, new stat (which could be poor??) 16 inch fan no viscous one. It idles for ages well under half. The rad leaks a little on a solder joint easy to fix but I wonder if a chinese upgraded ally rad is worth a try?? anybody used one??

I will run it with no stat and see what happens, it may prove something.

Also, the believed Janspeed system gets a very hot manifold..adding lots of under bonnet heat, should I wrap it?

2) My temporary repair to a few pin holes on the fuel tank top have now started weeping...or new ones! we are on Surrey Hants borders, does anybody know of a fuel tank repair place we could use in the winter. It still puts plenty of rust scale into our firth filter I regularly clean out. I have used in the past kits from the likes of frost to seal but had poor results in the long term with peeling coating blocking fuel lines after some years. My own TR6 a prime example.

3) probably still carb related, while coasting off the pedal and slowing down it is "lurchy" there is a knack, just touch the accelerator and it is smooth! any ideas?? it is irritating and not good for the drive train.

All in all though it drives tight, smooth and like a lowish mile car should! sort these little issues and we have a cracker.

Re: ongoing re commission of our RX7

Posted: Mon Jul 24, 2023 3:43 pm
by Porters2
yay
Nice one Russ, glad you are finally getting some fun out of the car, I am having a stainless tank custom made for mine but it is not cheap at £500 , this post has reminded me to give them a call and check on the progress.
Cheers Steve.

Re: ongoing re commission of our RX7

Posted: Mon Jul 24, 2023 4:21 pm
by rustyrescue
perhaps we should have asked around, 4 custom tanks the same pattern likely a lot less!

Re: ongoing re commission of our RX7

Posted: Mon Jul 24, 2023 5:29 pm
by Porters2
rustyrescue wrote: ↑Mon Jul 24, 2023 4:21 pm perhaps we should have asked around, 4 custom tanks the same pattern likely a lot less!
W(p
I’m having it made from my own pattern, laid under the car for ages making a cardboard and gaffer tape shape to fit under the spare wheel well, then made a set of drawings from that and sent them to the manufacturer to get one built.
With a bit of luck it will fit lol šŸ˜‚.
I left plenty of room for the heat shields and still managed to get approx a ten gallon tank.

Re: ongoing re commission of our RX7

Posted: Mon Jul 24, 2023 7:54 pm
by rustyrescue
cool...range of about 100 miles then :lol: though ours seemed very good driven gently for about 170 miles yesterday.

Re: ongoing re commission of our RX7

Posted: Tue Jul 25, 2023 10:47 am
by Casey
Great to see your car at "Simply Japanese" Beaulieu last Sunday. The only FB I could see in the entire show area!

Sorry you weren't around when I spotted your car, would have loved to have had a chat.
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20230723_114632.jpg (246.86 KiB) Viewed 63366 times

Re: ongoing re commission of our RX7

Posted: Tue Jul 25, 2023 10:57 am
by Casey
rustyrescue wrote: ↑Mon Jul 24, 2023 11:49 am
3) probably still carb related, while coasting off the pedal and slowing down it is "lurchy" there is a knack, just touch the accelerator and it is smooth! any ideas?? it is irritating and not good for the drive train.
I know exactly what you mean! I have experience of owning 2 x S2's and they both did this. My Series 3 doesn't though. It is quite irritating and, as you say, can't be good for the drive train. Having experienced it with 2 S2 cars, I thought it was just a "feature", but now, having subsequently had no issues with my S3, I do wonder if it was carb related on both cars? I didn't find a solution, just had to adjust my driving style to mitigate it.

Re: ongoing re commission of our RX7

Posted: Tue Jul 25, 2023 3:18 pm
by rustyrescue
shame we did not meet indeed...and somehow missed the whole field with the RX8 club!! interesting your two S2 did the lurchy thing. I almost wonder if it is too rich at idle, its like the engine could be hunting in gear?
Anyway....more pressing is our marginal cooling, going to remove the thermostat totally as a test.

Re: ongoing re commission of our RX7

Posted: Tue Sep 05, 2023 8:47 pm
by Hobbawobba
rustyrescue wrote: ↑Thu Jun 08, 2023 9:45 pm Im used to a lucas PI system on my car haha! not the same :lol:
Would that be a Triumph of some sort? :thumbup:

How did the cooling issue go? I saw you've swapped radiators

The 7's I've been in have always bucked whilst decelerating. I think my injected turbo set up even done it slightly. Although it has been a while since I drove it

Re: ongoing re commission of our RX7

Posted: Wed Sep 06, 2023 9:22 am
by gt_james
The chinese alloy radiators seem pretty good, few people using them with no issues. I have a mazdatrix one on the race car, I think an alloy radiator and E fan is an ideal upgrade.

make sure the oil cooler is working well too, oil cooling is a big part of the cooling system, not just the water.

I don't think these cars run right without a thermostat in, as the bypass hole becomes open all the time. Better to just order a new genuine one from mazda and swap it when you pull it to bits.

I use the comma super cold master ready mixed, after looking through the specs of a few, one of the few that doesn't contain 2-EHA chemical which other people on the internet have found eats silicone (coolant O rings)

Not sure if you have deleted the air pump, but you mentioned a janspeed exhaust so you probably have? In which case it might be worth checking your water pump belt isnt slipping, worth upgrading the pulleys and belts to the atkins multi rib belts. I always find they slip. I've never had much luck with the doubled up V belts either, they still love to slip.