Rotary4tw

iTrader: (3)

Brief heads up...

I went through this last week...

https://www.rx7club.com/showthread.p...=Cherry+popped

I was having a low boost problem last week due to a large hole in my intercooler piping. I solved the problem with ducktape, which held 10psi pretty well. The duck tape was starting to peel and melt away, so luckily my new hose arrived last night from scratchjunkie. Perfect hose, couldn't be more happy.

This morning I put on the hose, and fire the car up for work. 10 mins after warmup, I pull the car onto the freeway, and while in fifth gear, accelerate, likely nothing more then 3psi, but none the less the first spool of the morning. I hear a large popping sound, and I see my hood rupture up for a moment. I think... "Oh great, looks like I forgot to clamp down one of the hoses properly...."

I quickly pull the car over and do an inspection, and find that the hose that blew was the one on the left side, connecting down into the Y-coupling. It basically blew straight up, and took out one of my intake lines too. This is strange, because this hose has been holding well and has not been touched for the last week. It was holding just fine under 10psi, so I can't imagine why it would blow under 3.

I drive the car back to my place... about a mile away, to reconnect the hoses. When I get her in the driveway I notice she's leeking coolant, and after 2 mins of sitting in the garage, the coolant is all drained out of the system.

I tried to inspect the coolant leek, but I need to get to work and I don't have time to work on the car untill tonight. Hopefully there is just a hose somewhere or a gasket that may have blown open due to the preassure in the system.

This is the thing that I don't get... if it was boosting fine at 10-5-10 last week, full turbo's full preasure, holding it all fine without any issues... why would it all of the sudden blow under 3psi? I know it has something to do with the new hose that I put on...

Perhaps the ducktape was letting out air or something, and wasn't making a perfect seal, and then when I put the new hose on this morning, it locked the system up tight and exposed a new weakness.

Anyways, I'm just hoping that if you blew an internal seal (which is likely already the case too, but thats a different post) it wouldn't lose all of the coolant like this.

My questions for the good people of this forum, are... where should I start looking when I get home to try to find the leak... are there any problem area's that are weak points?

Here are some pictures...

Thanks for any ideas on what this may be. I'm just happy she didn't overheat and I heard the pop!

-Rotary For The Win

P.s. Each day the FD runs without issue really is a good day... :P

This is what blew, in an upward motion... both hoses were off and it was clamped down sufficiently and could hold 10 psi last week.

dgeesaman

iTrader: (7)

These things have a funny way of falling apart all at once. Usually the coupler that just now fell apart does so first - and one reason the later japanese (Efini) y-pipe assembly is bolted. So your repair options are: new coupler (75$!! from Mazda or much less for a used one), Efini y-pipe ($250), or silicone coupler ($50?). Since you had a boost leak before, it's not surprising another part has blown due to the higher loads. Make sure your band clamps and hose clamps aren't pinching into the rubber couplers - overtightening them can really kill the couplers quick.

The coolant and intake systems are entirely separate. Inspect the blown-off components very carefully - I'll bet one of them severed a coolant line when they blew loose. I hope they weren't damaged - you're in the area of belts, radiator fans, and many coolant hoses. Maybe it blew into the radiator and cracked an endtank, or bent the filler neck cap. In any case, you need to investigate like you planned and find the source.

Refill with coolant (or 100% distilled water, if you'ure unsure about the leak and don't want to make a pet-poisonous mess). If there is an Autozone on your way home from work, sign out their pressure tester tool rental. Test the system and test the caps. If you put 100% water in, leave it in until you're sure the leak is fixed and replace with regular coolant. I like the temporary distilled idea - it's summer and it will help clean the system out.

I can't recall if you said the hoses were replaced lately, but if you're unsure or they are original, call Ray at Malloy and get the set. It's a beeotch to do them all, but very important for reliability. Better to spend an extra few days in the garage and avoid a breakdown, IMO.

Dave

pugg57

dgeesaman, not to be a *****, but i'm pretty sure if you look at the top picture you can see what the cross-over pipe poped off the y-pipe and knocked off the coolant hose above it (its not just removed for the picture, that's where the "leak" came from, if i'm following him correctly.

dgeesaman

iTrader: (7)

I thought was an air hose - the hose that vents air from the air pump into the baffled section of the air box. But in the other pic, you can see the air pump hose more clearly. Plus, it's got that foam sheath that only coolant hoses have. But the hard line that he pointed to (runs to the ACV I think) is still unused.

<see below, I changed my mind again!>

PS: why would pointing out that make you sound like a *****?

Dave

Force13B

iTrader: (19)

I'm guessing you took all the caps off of all the radiator stuff right? But the silcone cuplers you can get from http://www.boostcontroller.com/ for like 26$ for both. I just bought new ones and they are currently on there way. As for the coolent check all coolent hoses. If you register you car with http://www.fd3s.cc he has the 93 manual in a pdf file that you can look at to maybe help you out.

DaveW

I don't remember which is which (DUH), but that hose with the padding looks like the BOV or Charge-Relief hose... The fitting it was attached to is only ~7/8 to 1" dia.

dgeesaman

iTrader: (7)

I'm still thinking here. There is an air hose that has sheathing on it - it's 13-751 of the parts list, group 1371. I think the one on my car has no sheathing anymore. As well, the radiator hoses are more curved, and you can see the radiator hose quite clearly in the second pic.

So I still would assume that's just the air pump/ACV return hose (his arrows are correct) and that the coolant leak originates elsewhere (but probably close by!).

Dave

pugg57

this is why pointint it out would make me sound like a ***** , because i said it and now i think i'm wrong

Force13B

iTrader: (19)

Check this part to.

alberto_mg

yup. i agree with pugg57 more or less. the coolant hose leakage is probably just coincidental.

regarding the coupler, you should be able to purchase a new silicon coupler from hosetechniques.com for under $10. you might as well replace all of your couplers since it looks like you are using the 12 year old brittle stock ones.

if i had to guess, i'd say your coolant leak might be the turbo coolant hoses (search on that) or the stock AST (see FAQs).

Since it sounds like you are a pretty new owner, i would say that the problems you are facing are not coincidental with how much boost you are running but due to the fact that you have a 12 year old car that might not have been driven for a while by the previous owner. 12 year old parts such as coolant lines and couplers are destined to brake once you start driving the car more regularly. wait until you start having boost issues from the original vac lines deteriorating

Force13B

iTrader: (19)

Woot for deteriorating original vac lines and drag queen RX7's

dgeesaman

iTrader: (7)

Coolant hoses, that is. Not the vacuum hose job - that's yet a different reliability/maintenance mod It's about 10 hoses that cost just over $100 and several hours of cursing to change.

The trick (IMO) is to use a knife to cut off the old hoses since they like to stick to the hard pipes. Also have a set of bent- or straight- needle nose pliers to move the clamps. Now that all the coolant is on the floor, you've taken care of step one

Dave

CantGoStraight

Hmmmmmmmmmmmm did it blow both ends of the x-over pipe off ??? and I'd be really concerned with how far he drove it with that coolant leak. There doesn't seem to be that much coolant on the floor for he system to be empty. Jack