'94 SC400 Hydro Pump Leak
#16
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So I found a seal manufactured by NOK that measures out pretty close. I haven't pulled the old seal yet but the shaft diameter is 16.85mm and the bore diameter looks to be 30mm. The seal I ordered is 17mm id and 30mm od so hopefully that will get me close enough. I believe part of the reason the old seal has failed is that the bushing the shaft rides on is worn and it appears it has allowed for some slop. Looking at the parts catalog again I am wondering if maybe the seal would be included with the end plate along with bushing. Plate part number 16932-50061 or 16932b in the picture.
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Okay I have two solutions for this pump and I am positive one will work. I just need to locate torque specifications if anyone can help me out? I have the 5 m8 main body screws, the banjo bolt, the pulley nut and the electronic switch and any other screws if listed. Thank you!
#19
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The 'end plug' is 14 ftlb
The 5 'front housing' bolts are 15 ftlb
The pulley nut is 43 ftlb
The solenoid valve is 28 ftlb
The suction tube retaining bolt is 10 ftlb
I'd post the pics of the manual but I don't have the software to extract the specific pages
Please let us know how it turns out
I couldn't get my pump apart - the pulley wouldn't come off - the puller kept popping off
The 5 'front housing' bolts are 15 ftlb
The pulley nut is 43 ftlb
The solenoid valve is 28 ftlb
The suction tube retaining bolt is 10 ftlb
I'd post the pics of the manual but I don't have the software to extract the specific pages
Please let us know how it turns out
I couldn't get my pump apart - the pulley wouldn't come off - the puller kept popping off
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zeus87gn thank you very much! My manual for my LS doesn't have this pump and I couldn't seem to find the specs anywhere. I should have the pump back together this weekend, I will get pictures of everything including the puller I used, it took way more force than I was expecting to pull the pulley off.
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So here it is. I decided a new cover assembly was the best course of action. The cover includes a new seal and bushing which in my case appeared to be worn out allowing some play in the shaft possibly causing a leak. This maybe why you can't buy just the seal. I have also included a picture and part number of a seal that looks like it may work, it fits in the cover plate but it is listed as 17mm I.D. and the shaft measures 16.85, not sure if that is enough to cause a problem. Still a good fit on the shaft. To do the o-ring on the actuator it will probably be easiest to break it loose while the unit is still bolted down. I did not find a replacement seal for the suction tube listed anywhere, mine was only weeping a little so I used FIPK on the flange so that should stop that leak. Make sure to clean up the shaft if needed with some 1500-2000 grit paper. Sorry no before picture of the pump, it took me about 2 hours to clean this thing, it was bad!
Last edited by Kraft; 09-12-16 at 09:21 PM.
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Cover sub-assembly 16932-50061
Main large o-rings 90099-14113 x2
Actuator o-ring 90099-14114
End plug o-ring 90099-14115
Suction tube o-ring ????????
Copper Union Seal 44327-12010
Should be all the seals you need to stop the leaks.
Main large o-rings 90099-14113 x2
Actuator o-ring 90099-14114
End plug o-ring 90099-14115
Suction tube o-ring ????????
Copper Union Seal 44327-12010
Should be all the seals you need to stop the leaks.
#23
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I was using the exact same looking puller and couldn't get the pulley off for nothing
The one oring you don't have a number for is the only one I was able to replace
I used one I had in this assortment I've collected over the years
Unfortunately I don't have a part number for it
So you didn't use the Honda seal in lieu of the replacement cover ?
The one oring you don't have a number for is the only one I was able to replace
I used one I had in this assortment I've collected over the years
Unfortunately I don't have a part number for it
So you didn't use the Honda seal in lieu of the replacement cover ?
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My puller has a little optional cone point that I pulled off, seems to help keep the puller more straight without it. Your pulley could have a bunch of oily dirt under the lip helping to cause the arms to slip off. You can try a hose clamp around the arms to help keep them from spreading. I really had to wrench on it and then it just went bang and came off. No, the seal was only $10 bucks and it is manufactured by NOK same as oem which is why I bought it. When I got to looking at the bushing in the plate it appeared to be worn. You can kind of see a wear transition on the bushing in the picture to the right of the oil grove. The bushing in the rear housing appeared to be just fine. With 190k on it I didn't want the chance of doing this job twice. It probably would be fine with just a seal.
#25
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Hey guys, I have a '94 SC400 and I have a small leak behind the pulley of the hydro pump used for the cooling fan. I don't want to convert to electric, as the stock cooling fan has always worked great (and still does). The shop manual shows an oil seal behind the pulley and I'm sure that's what I need to change. The manual shows step by step instructions and shows it as a non-reusable item (makes sense). But my Lexus parts catalog does not show that part and the guy at the Lexus parts department says it must come with the pulley. I can't believe that, as the seal is pressed into the housing behind the pulley. Does anyone know anything about this? I'm sure I could fix it if I could find the part ...
Thanks in advance!
Thanks in advance!
#26
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Hey Diego, it uses transmission fluid which can look like red coolant (like Dexcool, which is a little more orange). I still have my car and found a pump on eBay for $70.00. I bought another puller and managed to get the pulley off the spare pump but the puller broke when I tried it on the one in the car. I wanted to change only the front housing, as that is much easier to do. One of these days I'll look for another puller and try again ...
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Diego007 (05-04-19)
#27
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Well my car has 114000 mi last timing belt was when it has 109000 but at that time it wasn’t mine. Yesterday I check for the leak on the hydro pump and it’s really small leak and it’s just a hose but when Iam there I found that under the crank pulley at the bottom of the timing cover there’s a leak of coolant it weird cause when they change the timing belt they supposed to change the water pump and that’s was replaced like 5000 mi ago. Well the thing is now because it’s leaking coolant m, I think I’ll go ahead and replace the water pump and because I’m going to be there also replace the timing belt again. Any thoughts? Helps? Digital manuals of sc400 95 can somebody share by email. Or some recommendations at all thanks
#28
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Hey Diego, it uses transmission fluid which can look like red coolant (like Dexcool, which is a little more orange). I still have my car and found a pump on eBay for $70.00. I bought another puller and managed to get the pulley off the spare pump but the puller broke when I tried it on the one in the car. I wanted to change only the front housing, as that is much easier to do. One of these days I'll look for another puller and try again ...
#29
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Are you 100% sure that they did the water pump at the same time Diego? Seems odd that it would be leaking so soon. I had my water pump replaced twice --- also at the same time as my timing belt changes (I have a little over 260K miles on my car now). I never had water pump problems --- this was preventative maintenance. But if you are going to change the timing belt, you are right about replacing the water pump at the same time since most of the work is already done. By the way, I have run my cooling system unpressurized for many, many years now by leaving the radiator cap at the first notch. I have never once had a cooling system problem (leak, boilover, etc). Of course I always have the adequate coolant ratio in the system and am in south Florida essentially at sea level, so that helps. I'm saying this because this may help you get by until you decide to get the leak fixed.
#30
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Are you 100% sure that they did the water pump at the same time Diego? Seems odd that it would be leaking so soon. I had my water pump replaced twice --- also at the same time as my timing belt changes (I have a little over 260K miles on my car now). I never had water pump problems --- this was preventative maintenance. But if you are going to change the timing belt, you are right about replacing the water pump at the same time since most of the work is already done. By the way, I have run my cooling system unpressurized for many, many years now by leaving the radiator cap at the first notch. I have never once had a cooling system problem (leak, boilover, etc). Of course I always have the adequate coolant ratio in the system and am in south Florida essentially at sea level, so that helps. I'm saying this because this may help you get by until you decide to get the leak fixed.