civicpains

Honda Part: pipe, connecting
Part Number: 19505-P06-A00

Honda Part: o-ring (27.6x4.1)
Part Number: 91314-634-000

http://estore.honda.com/honda/parts/...n=&b=E++15&dl=

Davy_Jones12

Hi folks, this is my first post on this website. I have a '91 Integra LS Hatchback with a leaky connector pipe. I have all the part numbers:

Connecting Pipe: # 19505-PR4-A00
OEM: $35.90 (source Acura Parts | Genuine Acura OEM Parts | Acura Parts Cheap )

O-Rings: # 91314-PH7-003
OEM: $1.93 (source Acura Parts | Genuine Acura OEM Parts | Acura Parts Cheap )
Honda Autonation Dealership: $5.14
*NOTE: even though it's for an Acura, it shares the EXACT same part number with Honda.

I've been around, and know how to turn a wrench, I got a few busted knuckles too. I'm no moron, but am ignorant sometimes concerning these ricer hot rods. For instance: why do they all share this design flaw - a stupid little cheap a** pipe to connect the water pump to the thermostat? This has GOT to be the weakest link in this entire motor design, due mostly to the fact the pressurized coolant system connecting pipe is held in place via a single rubber O-ring on each end. What idiot thought THIS one up? That whole thing should have been soldered in place PERMANENTLY. But nooooooo, they gotta use a rubber O-ring that is held in place via friction and a teency-weency flange on the end of the pipe. PLUS, they got it shoe-horned in there tucked in tight underneath the intake manifold support bracket where you gotta take apart the whole motor JUST to get at it. The part don't cost $40 and you gotta spend prolly $400 on labor and extra parts to take the motor apart. Please tell me somebody wasn't smokin pot when they came up with this one.

(see below for the repair manual diagram).
engine block diagram for 91 B18A1 Honda motor, for a '91 Integra LS. The connecting pipe in colored RED, the O-rings are colored YELLOW.

Davy_Jones12

Turns out, BMW's have this EXACT SAME problem. What is wrong with the auto industry anyways? I just found a "fix" for this at bimmerfix.com, what they do is sell you a nipple that fits inside the leaking pipe, then you seal it in with what looks like RTV gasket goop. They say alls you need to do is remove the water pump to do this. But what they don't tell you is, you'll need to remove the valve cover, timing belt, all the other belts and the old water pump. AND, if you remove all that - guess what, you MUST replace all those belts and gaskets with brand new ones. On my car, a '91 Acura Integra, the gaskets I would need to replace are: the valve cover gasket set (which includes the valve cover gasket, and spark plug rings), all the belts, the timing belt, the timing belt tensioner, and the water pump O-ring. That would cost over $200. But the bimmerfix repair system COSTS $200, so to do it their way, we're talking a total of $400.

It might actually be cheaper to just take off the intake manifold, replace the offending connector pipe & O-rings, and replace the manifold gasket. I'm guessing $50 for all that.

holmesnmanny

This should only happen if you use tap water or non-distilled water in the system. If you are only using coolant, or half full strength coolant and half "distilled water", you shouldn't have this problem.

snobordboy

Davy Jones, not sure on the Integra, but on the Prelude we don't need to remove the intake manifold to do this job. Just unbolt the thermostat housing and the one bolt that holds the pipe to the block.

If you want to see a bad design, the early Porsche Cayenne engine had a bad water pipe on top and under the intake manifold, and it would leak behind the engine and into the transmission, so not long after you fix the pipe on the engine, the transmission goes out. That is not a cheap fix....

Davy_Jones12

Holmesnmanny, I always use 50-50 premix, the green stuff. But since this can be expensive when you have a leak, like what I was experiencing, after the leak drained off the good stuff, I refilled it with DISTILLED water, which didn't mater that much IF it leaked. So when I got it fix, my mechanic replaced it with 50-50 premix. Over time, those O-rings WILL fail. It's their nature.

Davy_Jones12

That's insane. I tried doing what you did, but because there's a mini nipple in the middle of the pipe, you can't draw it out.

Davy_Jones12

So I ended up taking to a pro mechanic, who promptly told me "You gotta remove the intake manifold, replace the old O-rings with new ones, then put it all back together, then do a pressure test." Cost me $250. Now my belts are all loose. WTH.

holmesnmanny

After removing the thermostat housing, there is one bolt holding the pipe to the block. Remove that and it pulls right off. Keep in mind there should be a water hose going from the pipe to the heater core.

snobordboy

I think the issue could be a difference in the B series of the Integra DavyJones is working with, versus our H series engines.

I know I have done both O-rings on my car without pulling the IM, just removed the thermostat housing, undid the bolt on the block, and popped the pipe out of the water pump enough to change rings, and pushed it back in. Actually did it like 4 times since it kept leaking, then I used Honda O-rings instead of the ones that came in my cheap gasket kit.

TopherD

Yes, this is an old thread however, I just replaced both pipes/o-rings (2003 Civic DX). All has been re-assembled and still leaking from the water pump side (pressure tested). Is there something that I am missing?

snobordboy

I have found that the ring used makes a huge difference. Are you using OEM Honda, or something else? If not OEM, go spend the extra few cents on the real thing, as they didn't use an off-the-shelf o-ring size.

TopherD

All parts purchased from the dealer p/n 91314-634-000. You can feel the o-ring fit into place and the 10mm mounting bolt aligns up, however as soon as you fill the system and pressure test, it still leaks from that area. The water pump/timing belt was just replaced.

TopherD

Not looking forward to it, but might have to remove the intake as you really can't see that area from under the car.

TopherD

Solved!!

In my case, the new o-ring ended being pinched. Discovered after pulling the connecting pipe, clear as day the o-ring did not seat correctly. So replaced with a new o-ring, pressure tested and was good to go!

BobLoblaw

They rot from the outside in from road salt etc. When I am king everything underbody will be non-corrosive steel and coated at factory. My cars all rot out after a couple years even with fluid film etc.