I have another suggestion for people who find themselves with a leaky air hose / duct / whateveryouwnanacallit.
The OE duct is still available (pretty sure) but may be cost prohibitive. Heavy application of tape works for a while, but it's a half solution. What I'm offering is a cheap, when you get around to it, three quarter solution.
Last year i had to repair an early 90's vehicle with a soft intake duct that had leaked due to degradation from oil intrusion because the original duct is NLA and i wasn't able to find any replacements without the same damage. It was an experiment because i had no other choices short of fabricating a new duct. That repair seems to be holding.
That was a 1991 VW Cabriolet with Digifant-1 fuel injection. No, it's not the same as a golf/jetta -- the intake is on the other side on the cabby. Oil vapor from the breather rots out the breather inlet on the duct, right at the arm-pits.
I just recently tried the same repair on a duct from an early 80's vehicle that is a hard intake duct not too different from the 80 series ducts. 1980 fiat spider with L-Jet, fwiw. I can get a new duct for $50ish but I don't wanna.
Cost? $7, time, elbow grease, cleaning products, hot water.
Basically you can glue it up with Aquaseal Urethane Repair Adhesive & Sealant. It's not hard to find - sold by Walmart, Cabela's, Amazon, etc.
Obviously you have to degrease and decrud the duct. Power spray at the carwash might help. I went for long soaks in solutions of dish detergent, Purple Power, etc. Has to be brushed to remove any loose degraded rubber from the area you are repairing. I took things slow - more than a week of long soaks and occasional cleaning. But there's no reason it has to be that slow.
If rubber rubs off the surface, scrub with dish soap and a scotch brite pad until it stops shedding.
If the rubber has a very rough or feathered / scaly surface like the soft duct i did, it turns out that this isn't a problem at all.
Final cleaning of the area to be repaired should be done with isopropyl alcohol until the rags come away clean. This didn't take very many repetitions for me.
Wait for the alcohol to evaporate, glob this stuff on - spread it with a popsicle stick or something if you need to - and wait several hours to a day for it to cure.
The quality of the bond is pretty impressive. The sealant has excellent wetting properties and gets right into the little nooks and crannies and micro-fissures. After it cures it seems to be pretty durable. Flexible but relatively stiff.
If the rubber was shedding previously, after the aquaseal has cured for a couple days you can coat it liberally with Wet Tire Shine and let it bake in the sun for a few hours. This is a trick homebrewers use to get their repurposed soda kegs to stop leaving black marks. Works great for me.
The OE duct is still available (pretty sure) but may be cost prohibitive. Heavy application of tape works for a while, but it's a half solution. What I'm offering is a cheap, when you get around to it, three quarter solution.
Last year i had to repair an early 90's vehicle with a soft intake duct that had leaked due to degradation from oil intrusion because the original duct is NLA and i wasn't able to find any replacements without the same damage. It was an experiment because i had no other choices short of fabricating a new duct. That repair seems to be holding.
That was a 1991 VW Cabriolet with Digifant-1 fuel injection. No, it's not the same as a golf/jetta -- the intake is on the other side on the cabby. Oil vapor from the breather rots out the breather inlet on the duct, right at the arm-pits.
I just recently tried the same repair on a duct from an early 80's vehicle that is a hard intake duct not too different from the 80 series ducts. 1980 fiat spider with L-Jet, fwiw. I can get a new duct for $50ish but I don't wanna.
Cost? $7, time, elbow grease, cleaning products, hot water.
Basically you can glue it up with Aquaseal Urethane Repair Adhesive & Sealant. It's not hard to find - sold by Walmart, Cabela's, Amazon, etc.
Obviously you have to degrease and decrud the duct. Power spray at the carwash might help. I went for long soaks in solutions of dish detergent, Purple Power, etc. Has to be brushed to remove any loose degraded rubber from the area you are repairing. I took things slow - more than a week of long soaks and occasional cleaning. But there's no reason it has to be that slow.
If rubber rubs off the surface, scrub with dish soap and a scotch brite pad until it stops shedding.
If the rubber has a very rough or feathered / scaly surface like the soft duct i did, it turns out that this isn't a problem at all.
Final cleaning of the area to be repaired should be done with isopropyl alcohol until the rags come away clean. This didn't take very many repetitions for me.
Wait for the alcohol to evaporate, glob this stuff on - spread it with a popsicle stick or something if you need to - and wait several hours to a day for it to cure.
The quality of the bond is pretty impressive. The sealant has excellent wetting properties and gets right into the little nooks and crannies and micro-fissures. After it cures it seems to be pretty durable. Flexible but relatively stiff.
If the rubber was shedding previously, after the aquaseal has cured for a couple days you can coat it liberally with Wet Tire Shine and let it bake in the sun for a few hours. This is a trick homebrewers use to get their repurposed soda kegs to stop leaving black marks. Works great for me.
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