VCCA Home Forums TECHNICAL - 1945 AND EARLIER 1937-1945 1940 SDSS pulling to right when braking

OK....I know I should have this one , and it`s bustin my chops ...so some suggestions? The master cyl. replaced 5K ago and all new brake wheel cyls. and parts. good (looking?) rubber brake hoses...pulled front wheels cleaned out brake cyl`s on both front wheels ...everything looked good except for gummed up ....cleaned all parts and rubber cups looked real good .... Bleed brakes per manual.....slight pressure on brake peddle , showed both sides- wheel cyl`s moving the brake shoes out ...Put wheels back on -adjusted all shoes perfectly ...still pulling to right. This happens with the SLIGHTEST of brake pressure , so I`m ruling out suspension problem. It had new front end work done 5k ago and it is very tight as far as steering . Pulled apart again ...also the back brakes ...cleaned out the brake cyl`s there ...re installed it all and adjusted the brakes up all the way around ...bleed per shop manuAl again ....pedal great, no spongyness....still wants to pull to right ......if I hit the brakes HARD a few times , it want to brake more normally , but soon wants to go back to the right hand pull. I heard that maybe a rubber brake line could have deteriorated and a flap inside causing problems?? I`m tired and stumped at this point and not sure what to check next....all wheels adjusted right ...been doing this for years I`m 68 , so , this all should be a no brainer for me ....also tried loosening adjustment on each front wheel seperately and no change....Shoes are all very new..maybe 2000K on them ...I sanded the front shoes and roughed up the drum inside to give a nice even grip on both sides...the right side showed more gripping and the left side little compared ...OK ....what do ya think?? Thanks, David

Try switching from side to side, the big pull back spring that runs fron shoe to shoe.

I had a very similar problem with my 38 pulling to the left. The problem turned out to be a faulty leading brake shoe with the material at the top uneven and protruding about the rest of the surface. I used a file to level it and the problem has been resolved. here is a link to the thread. Brake Pulling Problem . I was able to correct it after reading Chevnut's post.

I will try switching the return springs as Gene has suggested ....but as HARD as they are to get on ,I can`t see how that would be the problem.....The brakes were working fine when I took it out of winter storage ...then after the first time out ...this started ....still stumped ...but I will be pulling the front wheels and drums ...once again and continue on ....any more suggestions?? I`ll let you all know if I get it ...thanks David

Perhaps some grease soaked into the lining on one shoe.

what kind of fluid are you using

You will notice in the thread that I referenced in my post, that the brakes would return to normal after some hard applications at a very low speed. After several days the problem would return.

I have the front end up, and drinking a few beers thinking about it .....decided I`d wait a day or 2 for some more input from the chat before I pull the drums for the 4th time. I think I`ll put on new brake shoes ...I did spray shoes with brake cleaner a couple times and lightly sanded the shoes and drums. Does`nt that usually work for shoes that are slightly oiled-dirty? I had dot 3 in and had some dot 5 syn ...so I pumped the system clear and filled with dot 5 syn. No leakage that I can see.....did not mix . All bleeders flowed well ...would`nt that indicate that the wheel cyl`s are getting the fluid equally? I did see both sets of shoes moving without the drums with a little peddle pressure. Thinking new shoes next ??? ~D

I had the same problem with my 37. The problem was the wheel cylinders. Huck brakes are notorious for the pistons to hang up. A good cleaning and sanding with fine paper solved the problem.

i had the same problem with my 54 with the dot 5 had to take it out no problem sinse

OK ...today I`m pulling the drums again and going to check and see if there is a piece of crud in the holes of the wheel cyl`s. Clean again ...sand shoes and drums ..inspect shoes for some sort of problem ,,although these shoes worked well for 3 years up until a few weeks ago..switch return springs....and bleed again and give it a try ....again....

Dot 5 brake fluid has a problem that is not widely known. It tends to form and hold air if the seals on the wheel or master cylinders are not tight enough. The air migrates into the fluid. Heat causes the bubbles to expand holding the brake shoe close to the drum. It also causes spongy brake pedal. Despite the claims Dot 5 is not the best fluid for all brake systems.

Though I have owned some Dot 5 fluid for some 50+ years have still never installed in a vehicle. Our group did the testing 55+ years ago for our sister company when the silicone fluid was developed.

chipper i was hoping you would explain on mine the dot 5 seem to do something to the rubber parts causing a lot of bad stuff like pulling on the front and rear and lock up . even though they were major parts they could be foreign after changing the rubber parts flushing all parts and putting dot 3 in no more problem

The rubber brake cups were led natural rubber. Not sure that a more modern elastomer is now being used. Either way all brake fluid is supposed to pass several tests that include essentially no cup swelling submersed in hot brake fluid. Maybe the silicone brake fluid was contaminated, not the correct fluid or the test was fudged. Can't tell you for sure but it sure didn't work as it was supposed to. Last I knew the company I worked for is still the # 1 world-wide manufacturer of brake fluid.

Good information on all the possible problems causing this pull to the right..thank you !...I had dot 3 in there for over a year with no problems ....when I started on this fix , I went to dot 5 syn...so, that`s, that for now. I`m putting in new repair kits in both front wheel cyl`s....new rubber brake hoses....cleaned and sanded the shoes and drums...cleaned out holes in brake cyl`s....I did get a small amt. of gunk out of the left wheel cyl. fulid entry hole....maybe that caused a slight restriction ...making the right wheel to pull?? anyway , I`ll keep ya`ll posted after next test. The all new brake work done 5 K miles ago was done 21 years ago ....so I`m thinking the rubber hoses could be involved

If I would have known the last work was done over 20 years ago I would have had different thoughts. That a long time to go with Huck brakes and wheel cylinders.

Thanks Gene and O216 for the help on this one ....yes the years were a factor I guess....IT`S FIXED .... this time I put repair kits in the Front Wh. Cyls.... 2 new retracking springs on the shoes...3 new brake hoses ...and old 216 ...pulled 1 shoe and took off a bit of material , that could have been a problem too. Cleaned out the rear Wh. cyls, pumped a lot of fluid through ( have bled it a few times) , so , not sure the exact cure , but the system needed some TLC. Way too much time on that fix....but getting to know the brakes better and better ....the springs I got from Obsolete Chevy parts , were about a 1/4 in. shorter in the spring material( the twisted part)...making the new ones very tight ....I don`t know if they are right , but I did get them on.. how? ...a LOT of cussin for sure ,,at least I put some gloves on for a change....~D

forgot to mention ...chevy 1937..I think you were probably right about it being the wheel cyl`s....and Chipper and PRod I`m not sure what to think about the dot 5 ...I had it for my bikes and used it, and now wish I had`nt....I`ll have to see how that goes and will report in if I have more problems ...Thanks again for the help!!

There are plenty of folks that have been very satisfied with DOT 5 brake fluid. Has a few drawbacks like eating brake light switches but in total has proven to be a good product. Just not good enough for me to use it yet.

dot 5 does eat brake light switches. I've replaced the pressure switch on my street rod several times. I now have a mechanical switch.
Sid

I changed my 1939 to a lever switch also.
From what I have read the Silicone fluid coats the contacts in the switch. Other than that I have had no problems with silicone.

Thought I had it fixed ....let it set for 5 days and took it out today for a test , and first time I braked it pulled again pretty hard to the right. After replacing return springs, hoses , and new whl cyl. kits and everything all cleaned and lubricated, all that I can see left to replace are the brake shoes.....could the master cyl cause this? It was replaced in 1995 when the wh. cyls,and hose were replaced. I put new shoes on 3 yrs. ago, but may have some contamination ....I used brake cleaner on them twice and sanded them and the drums too. ....After a few good stops , it brakes normally....what do ya think??? ....shoes ....Master cyl.? the pedal stays up firm , no drop

If brake fluid or grease ever soaked part of the linings it can not be "fixed". The fluid/oils will keep resurfacing and cause the problem you are describing.
Yes, replace the shoes....and I just hate installing shoes on Huck brakes.

You could try swapping shoes left for right and carefully road test. If the problem stays it most likely not the shoes.
Tony

OK then...looks like I will replace the brakes next and I too am not looking forward to that . I mentioned the springs I got from Obsolete Chevy are VERY TIGHT . Is a suitable tool available to do that easily . I used vice grips , a lot of sweat and cussing....don`t want to do that again. So...no one thinks the Master Cyl would cause a pull ? I`m taking a break for now , but will report back on my progress.....need to wait out this heat wave awhile ...Thanks for the replies