Gary Lewis Posted June 14, 2023 Share Posted June 14, 2023 I'd think if there's enough fluid to splash out the port in the bottom isn't sucking air. You're right. If the rust isn't too bad you can file the master cylinder flat and bend the bail if the lid isn't tight. If I was going to replace it, I'd buy the $58 later ('87 up) MC from U-Haul on eBay and never have to deal with rust again. Hopefully it isn't leaking out the back into the booster. I agree, I'd go with the later model MC. In fact, I did. And I'm not about to go back. Link to comment Share on other sites More sharing options...
ArdWrknTrk Posted June 14, 2023 Share Posted June 14, 2023 I agree, I'd go with the later model MC. In fact, I did. And I'm not about to go back. Your's came with the residual pressure check valve in the rear port, correct? (because that's important, and you have to swap the lines front to back) I just did a quick check of U-haul's storefront and didn't see it in the first 100 pages. 🙄 I hate to give out of date information.... Link to comment Share on other sites More sharing options...
Gary Lewis Posted June 14, 2023 Share Posted June 14, 2023 Your's came with the residual pressure check valve in the rear port, correct? (because that's important, and you have to swap the lines front to back) I just did a quick check of U-haul's storefront and didn't see it in the first 100 pages. 🙄 I hate to give out of date information.... Yes, it did. And the lines swapped easily. Link to comment Share on other sites More sharing options...
gaveasky Posted June 14, 2023 Author Share Posted June 14, 2023 I'd think if there's enough fluid to splash out the port in the bottom isn't sucking air. You're right. If the rust isn't too bad you can file the master cylinder flat and bend the bail if the lid isn't tight. If I was going to replace it, I'd buy the $58 later ('87 up) MC from U-Haul on eBay and never have to deal with rust again. Hopefully it isn't leaking out the back into the booster. Would you kindly post a link to this MC you found on ebay? The gasket improved my situation (brakes work a lot better now, but still leaks from the MC lid) but the edges are pretty rusted so I think a new MC should be my next step. I also would like to find motorcraft ZD-1 glowplugs to replace soon (I hate to keep starting this truck with cosby sauce) and set up my momentary switch to bypass the presumably broken glow plug controller. Do you know of any place that sells those plugs? Link to comment Share on other sites More sharing options...
gaveasky Posted June 14, 2023 Author Share Posted June 14, 2023 Would you kindly post a link to this MC you found on ebay? The gasket improved my situation (brakes work a lot better now, but still leaks from the MC lid) but the edges are pretty rusted so I think a new MC should be my next step. I also would like to find motorcraft ZD-1 glowplugs to replace soon (I hate to keep starting this truck with cosby sauce) and set up my momentary switch to bypass the presumably broken glow plug controller. Do you know of any place that sells those plugs? Another question which arises when searching rockauto for brake master cylinders is that they are divided by GVW over 8500lb and under 8500lb On my doorwell sticker my GVWR reads 8600lb so I assume I must find one suitable for: -4x4 -2 piston front brakes -GVW over 8500lb Link to comment Share on other sites More sharing options...
ArdWrknTrk Posted June 14, 2023 Share Posted June 14, 2023 Would you kindly post a link to this MC you found on ebay? The gasket improved my situation (brakes work a lot better now, but still leaks from the MC lid) but the edges are pretty rusted so I think a new MC should be my next step. I also would like to find motorcraft ZD-1 glowplugs to replace soon (I hate to keep starting this truck with cosby sauce) and set up my momentary switch to bypass the presumably broken glow plug controller. Do you know of any place that sells those plugs? As I said above, I can't find those master cylinders right now on U-haul's storefront. I did post link in the marketplace thread back around Christmas. Maybe they are all sold? I'm certainly not the IDI expert. Perhaps Gary can hail Jonathan to this thread? I know he prefers Beru to the Motorcraft glow plugs but I don't know where he gets them or what he does about a crapped out glow plug controller. Link to comment Share on other sites More sharing options...
gaveasky Posted June 14, 2023 Author Share Posted June 14, 2023 As I said above, I can't find those master cylinders right now on U-haul's storefront. I did post link in the marketplace thread back around Christmas. Maybe they are all sold? I'm certainly not the IDI expert. Perhaps Gary can hail Jonathan to this thread? I know he prefers Beru to the Motorcraft glow plugs but I don't know where he gets them or what he does about a crapped out glow plug controller. Ah! my bad, I misread what you wrote. Thanks for the advice so far anyway it has been massively useful to me. Link to comment Share on other sites More sharing options...
ArdWrknTrk Posted June 14, 2023 Share Posted June 14, 2023 Another question which arises when searching rockauto for brake master cylinders is that they are divided by GVW over 8500lb and under 8500lb On my doorwell sticker my GVWR reads 8600lb so I assume I must find one suitable for: -4x4 -2 piston front brakes -GVW over 8500lb Yep. Usually the break is o/u 7,000 lbs. This is the difference between the "light duty" (15/16)250 and the heavier trucks with a bigger (1 1/16") master cylinder bore. I don't see any M/C on Rockauto with the valve in place. Do you know the width of your rear brake shoes? If it's a 250 I assume they're 2 1/2" but I'd .want to know. Link to comment Share on other sites More sharing options...
gaveasky Posted June 14, 2023 Author Share Posted June 14, 2023 Yep. Usually the break is o/u 7,000 lbs. This is the difference between the "light duty" (15/16)250 and the heavier trucks with a bigger (1 1/16") master cylinder bore. I don't see any M/C on Rockauto with the valve in place. Do you know the width of your rear brake shoes? If it's a 250 I assume they're 2 1/2" but I'd .want to know. https://www.rockauto.com/en/catalog/ford,1983,f-250,6.9l+420cid+v8+diesel,1123669,brake+&+wheel+hub,master+cylinder,1836 In my limited wisdom, I believe the CENTRIC 13065047 is the only one on that website that explicitly states 4WD and weight above 8500lb. Rockauto seems to break between above or below 8500lb, and again my truck is 8600lb according to the sticker on the door something tells me a truck considered "over 8500" would be a bit more than 200lbs heavier than the cutoff point. Link to comment Share on other sites More sharing options...
ArdWrknTrk Posted June 14, 2023 Share Posted June 14, 2023 https://www.rockauto.com/en/catalog/ford,1983,f-250,6.9l+420cid+v8+diesel,1123669,brake+&+wheel+hub,master+cylinder,1836 In my limited wisdom, I believe the CENTRIC 13065047 is the only one on that website that explicitly states 4WD and weight above 8500lb. Rockauto seems to break between above or below 8500lb, and again my truck is 8600lb according to the sticker on the door something tells me a truck considered "over 8500" would be a bit more than 200lbs heavier than the cutoff point. I see now that the early cast iron master cylinders break at 8500. This is so Ford can include 8,600 gvw trucks .under federal guidelines. If you look at the later (87-93) masters with aluminum housings and plastic reservoirs the break moves down to exclude "light" 250's. I realize all this pedantry may be confusing but it really matters when you start swapping parts to get a 'factory upgrade' Link to comment Share on other sites More sharing options...
Recommended Posts