My 92 vx had a y8 swap running on a p28. It spun a rod bearing so i swapped in a y7 block with the y8 head. Direct bolt on. Ever since i put it back on its had this nasty coolant leak that i can't seem to find. Its under the intake manifold near the water pipe. I've changed the oring on the water pipe but i don't even know where to start since i don't have a clue where the leak is from, all i see is the drips and dried out coolant marks. Anyone wver had a similar problem or something? Been at this about 2 weeks now.


http://i1067.photobucket.com/albums/...A7CD776039.mp4

http://i1067.photobucket.com/albums/...A7AF7BA023.mp4

2 different shots of my car. I believe the lower video is before my drive home. Upper is after. Both are with the car off.

 

Is it coming from near a hose by any chance? There are a few different spots near the water pipe where a hose could be dripping. I am pretty sure there are some misc coolant hoses running back there, just smaller ones.

 

Yep like he said check your hoses.

Been there.

 

And by hoses I do not just mean the 2 radiator hoses.

 

I had replaced a main hose and checked them out. They are all good. It seems to drip from the water pipe and along the block. My guess was that plug looking thing next to the oil filter but I'm not sure if thats even a coolant passage.

 

Yeah I've checked all hoses near the intake and heater hoses, iacv hose, fitv hose and all of them below the intake mani

 

Is the water pipe itself cracked? I would say take it off somehow block off one end of it, fill it with water, block off other end, dry the pipe, observe.

 

It didn't appear to be cracked. I removed it yesterday to change the orings. I'll remove it again today. Odd thing is that it never had a single leak on my y8 block, but first startup on the y7 block it leaks.

 

Any idea if d15's and d16's use the same size water pipe? Might just get one at the junkyard tomorrow to be safe. I'm heading there for a headlight switch as well.

 

That's not a good sign... except for the fact that you had to remove everything, so I wouldn't blame the block or anything like that just yet. Probably just a hose didn't get quite on all the way..? Maybe drain the system, remove the hoses one by one and reattach. I know it sounds time consuming but it is the cheapest test.

 

I would assume they do, but not 100%

 

Its worth a shot. I'm going to remove my intake manifold and check for signs of leaks and try to put all the hoses on again. Can't hurt at this point. I'll start today and finish tomorrow before work. I'll post up any progress i find/make.

 

I think before i remove anything I'll head to autozone and borrow a pressure tester.

 

Hoses or maybe even the fan switch??

 

What you need to do is get a jack and jack up the whole front end and put jack stands at the lift points, get under the car when it's cool, and get a view from there. I hate to say it but the videos are pretty much worthless. One thing I did see is you are leaking oil from your PCV overflow tank at the hose clamp (shown in the first video). You may want to address that. The other thing I noticed is that you are not using 'Honda' coolant. Honda's coolant is BLUE and I mean really blue. It would make a leak much more noticeable.

 

Fan still kicks in properly so thats still good.
I've jacked it up and been checking it but from the angle its hard to pinpoint the leak. I don't use honda coolant. I use prestone. It works and i get it cheap.
I'll take care of the oil leak. Thanks

 

Apply pressure to the cooling system and get under the car and check it out. problem solved

 

Check the connecting pipe:

 

I didn't mean the switch itself. I meant the o-ring on it that seals it off.

 

there are also 2 places on the side of the water pump that are designed to leak if the seal on it goes.
both will leak out to the inlet side
1 points up at 45deg and other points down at 45deg

 

I decided to remove the whole pipe for inspection. I found this


Now I don't know if that small thing could cause this leak, or if this leak is from that plug looking thing. I'm not even sure if water passes by there or if its an oil passage.
Also saw this on the water pipe near the thermostat, looks like dried up coolant.

Any ideas anyone?

More shots of that leak under the intake manifold, behind the block.


That black smudge is only my flashlight.

 

Just replace the connecting pipe and the two O-rings and then go from there.

 

Also i'm not sure if using the water pipe from a y8 on the y7 block would pose a problem? And which is recommended for a new pipe on my y7 block.
All help is appreciated.

 

I have both o rings from honda. Wheres the next best place to get an oem pipe? The parts dealer at power honda said he wouldn't have any for a while

 

Check on the Majestic Honda site whether the connecting pipes for the Y8 and Y7 have the same part number. They may be the same.

And I also think that the connecting pipe for the auto versus manual transmission is different.