• Welcome to ClassicBroncos! - You are currently viewing the forums as a GUEST. To take advantage of all the site features, please take a moment to register. It's fast, simple and absolutely free. So please join our community today!
    If you have problems registering or can't log into your account, please contact Admin.

Need Wiper Vacuum Solution

DrDanWWW

Jr. Member
Joined
Apr 7, 2019
Messages
68
My '66 vacuum wipers struggle for vacuum. To begin, I took a part and cleaned up the vacuum wipers. I did not rebuild with a new kit. Next, I have the stock 66 fuel pump. Question: I do not know how the fuel pump vacuum works: do both tubes on top - ports "suck in" ?
 

U13FL735

Full Member
Joined
Oct 3, 2018
Messages
177
No, Its a vacuum booster pump. Engine vacuum from the intake manifold connects to the top port of the pump that is furthest from the engine block. The port closest to the block is the boosted vacuum that goes to the wiper motors.
 
OP
OP
DrDanWWW

DrDanWWW

Jr. Member
Joined
Apr 7, 2019
Messages
68
Unless you're stuck on remaining totally stock check out the electric wiper swap.
Right. I actually own the Tom's electric kit. I just think they look too clunky IMO. And I think the old vacuums look better, by which i mean smaller. I may have to end up installing the electrics.
 
OP
OP
DrDanWWW

DrDanWWW

Jr. Member
Joined
Apr 7, 2019
Messages
68
Okay thanks folks. It looks like I am piped correctly then. If I want to use the vacuum wipers then I probably need to do a couple of things: 1, rebuild/refresh the old wipers. And 2, make sure I don't have a vacuum leak anywhere and clamp the wiper vacuum hose.

So the 170's intake manifold vacuum feed tube is helping the fuel pump vacuum booster pump, right? And so the distributor is also helping by requiring vacuum?
 
Last edited:

okie4570

Contributor
Bronco Guru
Joined
Jul 16, 2012
Messages
9,536
Loc.
NW OK
Okay thanks folks. It looks like I am piped correctly then. If I want to use the vacuum wipers then I probably need to do a couple of things: 1, rebuild/refresh the old wipers. And 2, make sure I don't have a vacuum leak anywhere and clamp the wiper vacuum hose.

So the 170's intake manifold vacuum feed tube is helping the fuel pump vacuum booster pump, right? And so the distributor is also helping by requiring vacuum?
You should have a small hard line from the passenger side of the carb to the back side of the distributor. Very possible you've got pin holes and rot in the tube up to the wipers in the windshield frame as well, especially if it's original.
 

U13FL735

Full Member
Joined
Oct 3, 2018
Messages
177
Okay thanks folks. It looks like I am piped correctly then. If I want to use the vacuum wipers then I probably need to do a couple of things: 1, rebuild/refresh the old wipers. And 2, make sure I don't have a vacuum leak anywhere and clamp the wiper vacuum hose.

So the 170's intake manifold vacuum feed tube is helping the fuel pump vacuum booster pump, right? And so the distributor is also helping by requiring vacuum?
Your right, except that the distributor uses straight engine vacuum only to adjust engine timing
 
OP
OP
DrDanWWW

DrDanWWW

Jr. Member
Joined
Apr 7, 2019
Messages
68
You should have a small hard line from the passenger side of the carb to the back side of the distributor. Very possible you've got pin holes and rot in the tube up to the wipers in the windshield frame as well, especially if it's original.
Yes, I have the hard line from the intake to the fuel pump. All my hoses are new. But I really should check them all. The old wiper vacuum hose is long gone. I bought a new Gates Rubber hose part number 27040 at OReilly's. That's how I tested the vacuum wipers. Even tho the hose is new, I should clamp it - it went on too easy.
 
OP
OP
DrDanWWW

DrDanWWW

Jr. Member
Joined
Apr 7, 2019
Messages
68
Your right, except that the distributor uses straight engine vacuum only to adjust engine timing
Thanks U13FL735. I guess I am wondering if my fuel pump's vacuum is somehow diminished or cheated somehow - other than leaks. I just need to keep checking all the hoses and tubes and fittings and such.
 
OP
OP
DrDanWWW

DrDanWWW

Jr. Member
Joined
Apr 7, 2019
Messages
68
Well, I gave up on the vacuums. I installed the electric wiper kit. I still don't like the look. But I have dependable wipers. Now I can get my vehicle inspection and state registration sticker. Now if I drive some distance, at least I drive in the rain. I should probably put the hard top back on.

I think I will fiddle with the vacuums a bit more and see if I can get them working properly. I will get the little cheap paper gasket kits.
 
Top