Hi folks. I finally got around to installing the donor strut towers with the jumbo brakes from a 92 960 with ABS.
This was installed on an 86 740 turbo that had the dual piston girlings.
I did everything described at brickboard, and now I have little to no front brakes. This included disconnecting unused brake lines, and blocking those ports with ATE plugs.
I fully flushed and bled the entire system. I have a good hard pedal, but very little brake action.
I did see a note on swedishbricks where someone said that you can't put an ABS caliper on a non ABS system. I can't see why not, the ABS stuff is separate from the caliper, isn't it?
I need help with this, I'm down to this one car, and I would like to be able to stop..... (so would the folks in front of me....8*)))
Are you sure you used the correct ports in the calipers, and that the calipers are not plugged up? I had thought the pressures were the same whether ABS or not, but I don't really know. Not really sure what the point in upgrading the brakes is, Volvo used very good brakes right from the factory, I've never found them to be inadequate, even when towing a boat.
Glenn has already given us the answer (use of calipers designed for ABS).
Antilock brake systems can, and frequently do, operate under *extremely* high pressures (much more than non-ABS).
I can only hazard a guess that this is the case for the Volvo in question, but I sure as hell *wouldn't* recommend the mixing and matching of ABS/non-ABS brake components on any car I drove.
Can only suggest either getting the correct components (which unfortunately may involve replacing both the calipers *and* the rotors) and fitting them to the car, or re-fitting the original 86 spec brake components as soon as possible.
Hi guys, a bit later than the fix, but here's what I did..... (sorry for the length.........8*)
I had 2 goals, one was to end up with 2 piece hub/rotor setups, and to upgrade to jumbo brakes. What started this is that the original setup on the 86 740 was starting to act up, pullling, and pedal pulsating, and I didn't want to spend money on the 1 piece rotor/hub.
I had obtained the strut towers with brakes from a 92 960. I installed that with the jumbo brake setup per the brickboard. The 'yard calipers were frozen, so I stole the calipers from my 940 which had recently died. These were known good calipers, less than 6 months old. After bleeding, etc. I had a very stiff pedal and no front caliper action.
I did drive it a couple of days that way, with careful planning for stops. Braking did get better as things settled, but it wasn't right. After my last post, I went and found a pair of rotors (2 piece, 10.25") for that car, thinking that if the orig. caliper and bracket and this rotor didn't work on the 92 strut and hub, then I'd get the conversion hubs and use them there.
It worked!!!!!!!!! I pulled the 960 stuff, and put on the new rotor, with the original bracket and 2 piston caliper. It all lined up, and fit right. I was hoping that volvo had maintained a standard distance for everything, and they had. In the process, I found that all 4 pistons worked correctly, and the problem was that the pads weren't sliding, ie were frozen to the brackets. So, after cleaning that, and lubing things, it's back to normal. (this is on the 960 strut towers which bolted right in!)
James:
Yes, I used the ports as pictured on the brickboard. If you go to 'brakes' on the first pulldown, in that section is the upgrade section. In there, there is a specific paragraph that tells about using ABS calipers on a NON ABS system. I guess that's the part that I don't understand. Everything else that I've found on the brickboard has been spot on, so I still think that there might be something amiss on my particular car.
There is one slight possible clue to this. My BRAKE light is on. Last night I did the procedure to reset it, and it didn't work. There is a bit of corrosion where the switch sits, and I'm wondering if lack of movement of the piston could affect things.
Pressure. I had heard warnings over the years to be careful of opening up ABS brake systems as they held pressure until relieved and were dangerous because folks were getting brake fluid forcefully injected under their skin when they opened a system. Along with that was the news that volvo didn't work that way, that the pressure got relieved. (?) So, maybe the systems do operate at higher pressures, there is a pump that does the pulsing.....
As to good brakes, yes, they are ok, but the jumbo setup fixed a lot of things that I thought caused problems with the 2 piston setup, plus larger pads and rotor surface, not to mention a thicker rotor. I've had both 740's and a 940, and found the 940 brakes to be a bit better.
Andy: Thanks for the reply, your last words about restoring the original 86 stuff helped me realize that the 2 pc rotors just might work on the new hubs. As to mixing and matching, it's been going on for years, and can result in a better setup. Look at what the hot rodders have done for years.
I'm not done. If I do find the answer, and find that it can work, I have the parts to put the jumbo setup back on. For now, it's keeping the 86 running reliably until I can find a replacement for the recently deceased 91 940. And if I don't find the answer, I'm happy with where the 740 is now, and I have spare parts for my next 940.
Sorry for the extreme length. I do ramble on a bit............
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