Strategic brake bleed possible?
 

Doing front overhaul of 86 brakes including calipets and soft lines. I dread the thought of 4 wheel bleed so wondering if it is possible to "quickly" unscrew inboard soft line fitting and put a rubber plug on hard line end.

Then install new calipers and soft line and "quickly" connect soft line to hard line. I know at this point air in soft line/caliper but do ypu think then I might be able to just do front bleed on each wheel?

Crazy? Or maybe doable??

Thanks. Randy

CRAZY!
Front brakes will be practically useless. Do it right, bleed the whole system after the brake work.

Dave

Bleed farthest line first at the caliper bleeders.
RR, LR, RF, LF. ( left hand drive).
Prior to each bleed have assistant pump the brake pedal three times SLOWLY and hold.
For tough to bleed situations, ie new lines, open and close bleeders quickly multiple times. This helps trapped are to move to the bleeder.
You can also be your own assistant using a length of wood between the seat and pedal to hold the petal after the three SLOW pumps.

I don’t take any risks with brake work. NO SHORTCUTS.
Do it properly for peace of mind.

And... take it from someone who's been there - you MUST bleed the brakes every couple of years because the fluid goes bad and gets sticky. And there are moving pistons in that entire system that don't like sticky. Especially in the "balance valve". You will be doing the right thing for the car and your life when you bleed the brakes.

Bill

I guess the opinions are clear 😂 Problem is I am working in super confined space and can't get car up on 4 stands, just two at a time. So nearly impossible to access rears.

I guess I will replace the parts and take car somewhere with a lift and pay to have full flush of system
Randy

One thing I do is heat the bleed nipple, and allow to cool. A snapped nipple on a rear caliper is bad news.
Rob

This is something you don't want to hear. But since you are going to have the brake lines open it is an ideal time to flush out the Master Cylinder and all the lines. All cars recommend this as preventative maintenance but hardly any one ever does it. Look in your Master Cylinder, is the fluid black? It should look like Apple juice. There is an excellent DIY video on YouTube by “Chris Fix” on how to flush and bleed your brakes without an assistant. Last summer I did both of my Jaguars, it takes about $20 worth of brake fluid per car and I spread it out over several days but if your lucky it will be the last time you ever have to do it.

Why the aversion to brake bleeding? It necessary and effectively changes your break fluid which is a maintenance item. In any case get a 1 man bleeder from Amazon, like the ones shown below. I would STROGLY suggest you remove the bleeder screw and pre-fill the caliper with brake fluid. This can be messy but well worth the time. Then put some teflon tape or pipe dope on the bleeder screw threads before you put it back in the caliper. Then put it all back together quickly and let it gravity bleed to 10 min using a hose right into an used water bottle. Keep an eye on the MC fluid level. This gets all the air out so the Master cylinder doesn't over extend and destroy the seals. Then do the pressure bleed with the check valve or vacuum bleeder.

If you have shop air the vacuum bleeder in the 2nd pict is the way to go. I use this one now and it's great but requires shop air. Both techniques will work but the vacuum bleeder is way faster and almost eliminated the MC over extension seal problem.




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and pb blaster the bleeders a couple of times for a couple of days befroe applying heat. patience.....a lot of patience....

Aversion is based on difficulty of accessing rear bleed screws....in my work environment. I suspect the people amazed at my post have garages with lifts and all the good toys needed to work on cars😊

I don't..so as I said will swap out parts and take to my local old Jag place for proper flush n fill

Randy

hi: my butt is firmly planted on the ground as i work on the underside of my car as well. admittedly i had to remove the one of the rear shocks on each side to get a clear pathway but i get the impression that this is well within your ability.

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No worries..I am totally capable..but "removing shocks" to do a bleed...just saying this is a total pain

But keep flaming

You don't need to bleed the rear if you're only replacing the front calipers. The two brake circuits are completely separate and have been this way for safety reason since the late 60's. I just did this on a 12,000LB GMC motor home. I replaced both front calipers with larger units , bled only the front and left the rears alone, stops better then ever. I'll be getting to the rears later in the spring.

BTW, I dont have a lift or a garage with a high ceiling, or even enough room to remove and engine inside. I just get creative.
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No room for a engine hoist, out the bottom then.

You dont need to bleed the rears if you're replacing the fronts. Just prefill the front calipers and bleed them only. The hardest part about changing the front calipers is removing the caliper bolts. Wack with a hammer to great microcracks then treat them with PB blaster a day ahead. If you want you car to stop and feel better get EBC red pads. The part number is DP3262C

easier than it sounds. to remove: 1 top bolt and nut.....same for the bottom....pretty good bolt/nut access too...someone will have to do this to properly bleed the system so it might as well be you.....i've read your posts and you are very capable..... unless your rear shocks/spring are new, take the money you will save and apply it to new set of gaz adjustable shocks and springs....i really noticed the difference.

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To answer your question, I'm fairly confident that would work without affecting the rear brakes.

Followup finally

Got brake rotors, calupers and pads replaced along with new soft lines...all on front

Used Mityvac bleeder and seemed to work OK although the fittings for bleed nipples are crappy and loose.

So maiden voyage she stopped just fine but when I stopped and did a quick inspection I was shocked to see brake fluid seeping out from resevoir cover. Cover was on snug soooo...after another look it looks a bit overfull.

I will drain some out but wondering two things. Is the fluid in resevoir under any pressure that would cause it to leak out of cap and...does it heat up enough to expand in resevoir and cause leak?

Thanks

The master cylinder reservoir is not under pressure at any time, and in my experience, calipers/rotors heating up would not cause reservoir fluid to overflow. How full was it before you left the shop? Has/had the level gone down since you parked it?

Dave

Easy. Over fill. siphon off soe. or merely bleed a bit. At easiest calier will do it.

Carl