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-   -   Pressure pushing dipstick out???? (https://www.rx7club.com/1st-generation-specific-1979-1985-18/pressure-pushing-dipstick-out-934252/)

Joon-Pr 12-13-10 07:32 PM

Pressure pushing dipstick out????
 
So as I was reving my engine from the carb, I noticed a sound about every 10 secs that resembled a purge. I went to to Driver side & continued to listen & realised it was coming out of where the dipstick goes in & had been pushed out (the dipstick). I put it back in, reved it for about another 10secs & when I pulled it out it shot out & was def under pressure. I've noticed that on the Oil fill neck, alot of ppl put small filters or a catch can. Can it be The hose I have on mine isn't where it's suppose to be???? There's a substantail amount of pressure building & i'm pretty sure it's suppose to vent from somewhere. Here's a pic of how it's currently set up. Should I plug the nipple on the plate & filter the one on the neck??? I think that'll help w the issue......
Any & all input in greatly appreciated

http://i1031.photobucket.com/albums/...7/IMG_3166.jpg

deadphoenix52 12-13-10 07:44 PM

leave them both open. or put a filter on the filler neck and route the lower one to vacuum. like that your crankcase cant breathe at all

Joon-Pr 12-13-10 08:16 PM


Originally Posted by deadphoenix52 (Post 10365239)
leave them both open. or put a filter on the filler neck and route the lower one to vacuum. like that your crankcase cant breathe at all

So filter the neck & plug the lower one, Gotcha. Prob just block it off with a hose & screw, not sure where I can plug it for vacuum. Goodlookin out

trochoid 12-13-10 08:42 PM

You shouldn't be seeing that kind of pressure in the crankcase, time for a compression test. You have a side or corner seal leaking. If either one is stuck and causing the leak, Seafoam might help loosen it up.

Joon-Pr 12-13-10 09:07 PM


Originally Posted by trochoid (Post 10365307)
You shouldn't be seeing that kind of pressure in the crankcase, time for a compression test. You have a side or corner seal leaking. If either one is stuck and causing the leak, Seafoam might help loosen it up.

I recently added a bottle of alumasel to seal up a water seal that was causing my car to smoke alot upon cold start. Turned it on today for 1st real cold start & not a puff of smoke, I'm hoping the additive can help for that pressure issue as well

mazdaverx713b 12-13-10 11:42 PM

you do know there is a vent line on your firewall that you can vent one of those into correct?

deadphoenix52 12-14-10 12:40 AM


Originally Posted by mazdaverx713b (Post 10365598)
you do know there is a vent line on your firewall that you can vent one of those into correct?

i may reroute my lower one to do this. right now its spliced into the vacuum for the brake booster.

trochoid 12-14-10 01:43 AM


Originally Posted by Joon-Pr (Post 10365334)
I recently added a bottle of alumasel to seal up a water seal that was causing my car to smoke alot upon cold start. Turned it on today for 1st real cold start & not a puff of smoke, I'm hoping the additive can help for that pressure issue as well

It won't. The oiling and cooling systems are totally separate and for good reason. When oil and coolant mixes it makes a very nasty frothy milkshake that neither cools nor lubricates well. Keep a nose on your dipstick. When compression starts bypassing the sideseals into the crankcase, the oil tends to become fuel diluted. You may need to change your oil more often.

Joon-Pr 12-14-10 06:55 AM


Originally Posted by mazdaverx713b (Post 10365598)
you do know there is a vent line on your firewall that you can vent one of those into correct?

No, not aware of that. This is my 1sr rotary, going along as issue arise. Do you know where exactly & plug which one into it, the one coming from the plate??


Originally Posted by deadphoenix52 (Post 10365660)
i may reroute my lower one to do this. right now its spliced into the vacuum for the brake booster.

So your planning on rerouting into the firewall??


Originally Posted by trochoid (Post 10365713)
It won't. The oiling and cooling systems are totally separate and for good reason. When oil and coolant mixes it makes a very nasty frothy milkshake that neither cools nor lubricates well. Keep a nose on your dipstick. When compression starts bypassing the sideseals into the crankcase, the oil tends to become fuel diluted. You may need to change your oil more often.

I've noticed on the oil fill neck & on the dipstick there's been that white milkshaky thing on occation. I've read that it's condensation that turns the oil into that & I shouldn't worry about it unless I see antifreeze mixed w it. Just gave her an oil change & I don't drive her much, should be good till the weather warms up again.... Ty

DriveFast7 12-14-10 12:01 PM

Crankcase pressure is typically a failed side seal.

KansasCityREPU 12-14-10 12:02 PM


Originally Posted by Joon-Pr (Post 10365856)
I've noticed on the oil fill neck & on the dipstick there's been that white milkshaky thing on occation. I've read that it's condensation that turns the oil into that & I shouldn't worry about it unless I see antifreeze mixed w it. Just gave her an oil change & I don't drive her much, should be good till the weather warms up again.... Ty

You won't be able to tell if it's condinsation or coolent. The way the oil and water/coolent get mixed together it just forms the milky spots. If you have a coolent leak, you'll see white smoke in the exhaust, small bubbles in the radiator or back pressure in the overflow, and the water level will slowly go down until you get a low coolent light.

Joon-Pr 12-14-10 05:37 PM


Originally Posted by DriveFast7 (Post 10366324)
Crankcase pressure is typically a failed side seal.

Any recomendations, seafoam??

DallasFC1 12-14-10 06:06 PM

Sideseal failure usually means, take motor apart, replace sideseals, check apex seals, and all the lovely rubber seals... OR, vent it well and run it till it pops. then you needs a full rebuild.

:)

Joon-Pr 12-14-10 06:27 PM


Originally Posted by DallasFC1 (Post 10366876)
Sideseal failure usually means, take motor apart, replace sideseals, check apex seals, and all the lovely rubber seals... OR, vent it well and run it till it pops. then you needs a full rebuild.

:)

The word "rebuild" doesn't sit well in my stomach.....
I'll try the venting (filtering the neck, any other suggestion?), not drive as hard & pray to the rotary Gods for @ least another yr w/o serious problems. The odds are prob Slim to none by the sound of this... Lol

coldy13 12-15-10 08:25 AM

How many miles are on the motor? The side seals are strong and don't break even under 20psi, the corner seals and back plate crack easily though. Vent the filler neck with a filter(mount it as high as you can, run a hose to it) or catch can and try the seafoam treatment, change the oil and see how it runs. It it doesn't run good or start when hot then check compression and start worrying about a rebuild.

Joon-Pr 12-15-10 08:42 AM


Originally Posted by coldy13 (Post 10367736)
How many miles are on the motor? The side seals are strong and don't break even under 20psi, the corner seals and back plate crack easily though. Vent the filler neck with a filter(mount it as high as you can, run a hose to it) or catch can and try the seafoam treatment, change the oil and see how it runs. It it doesn't run good or start when hot then check compression and start worrying about a rebuild.

Miles on engine are unknown, I purchased the car a yr ago & it already had undergone an engine swap. Prior owner said motor was streetporrted w about 30k but he wasn't sure.
Will do the filter, do u agree on blocking the nipple on the plate? (not that I'm doubting any1 just looking for as much info as poss.)
How should I seafoam down carb or gas tank??
Btw the car runs great & hasn't lost a step!. She starts right up everytime cold or hot, not a prob till date...

coldy13 12-15-10 06:08 PM

I think the nipple on the center iron is another vent, so by running a hose between the two you capped off both vents. You can do the seafoam however you want, 1/8 tank of gas pour in the whole bottle, pull a small vacuum line and let it suck in the fluid, or just slowly pour it down the carb. Marvel Mystery Oil is good for the engine too, 1/4-1/2oz per gallon of fuel, and 1/4-1/2quart in the oil will help keep carbon deposits from building up.

82FanTC 12-15-10 07:45 PM


Originally Posted by Joon-Pr (Post 10367767)
Will do the filter, do u agree on blocking the nipple on the plate? (not that I'm doubting any1 just looking for as much info as poss.)

Put a crank case filter on the top nipple and hook the bottom to a vacuum source, preferable with a PVC valve in the middle. Dont cap either one. Search "lung mustard" and you will find lots of info. However this will not solve your crankcase pressure/dipstick popping out.

Joon-Pr 12-16-10 02:31 PM

Thanks for the info guys, the search on "lung mustard" had alot of details...
I'll see what I do about the seafoam, seems to cause alot of smoke & I'm in an highly populated area

13x 12-16-10 02:37 PM

wow yeah leave those open mine are and I shift after the buzzer tells me and don't have an issue

Joon-Pr 12-19-10 10:24 PM


Originally Posted by mazdaverx713b (Post 10365598)
you do know there is a vent line on your firewall that you can vent one of those into correct?

So I noticed 2 nipples that barely stick out of the firewall both slightly over from center of car. Are those the ones you speak of?? I tried connecting the plate hose to 1 but couldn't get a clamp to bite, just left it hanging & will try again when I get the chance......


Originally Posted by 82FanTC (Post 10368818)
Put a crank case filter on the top nipple and hook the bottom to a vacuum source, preferable with a PVC valve in the middle. Dont cap either one. Search "lung mustard" and you will find lots of info. However this will not solve your crankcase pressure/dipstick popping out.

Actually I filtered the neck & left the plate hose open, let the car warm up & reved the shit out of it & when I pulled the dipstick no pressure what so ever. Poor engine wasn't breathing all this time, real test will come when I take her out for a hard drive...

rxtasy3 12-19-10 11:22 PM

as with any engine, the crank case needs ventilation. once all related items involving the rats nest removal, a pcv setup needs to be done to eliminate the chances of condensation forming in the filler neck. there's write ups on this procedure, which should have come up in the "lung mustard" threads. i did it many yrs ago and it completely stopped the condensation i was getting. i actually believe the pcv valve can be left out, cap one of those off and run a hose from the other one to the clean air side of the breather. all that's needed is a very slight vac draw on the crank case. when putting a pcv valve in line with the vac source to the brake booster, it reduces it to such a slight draw u can barely feel it with ur finger. that's why i think running a line to the clean air side of the breather will suffice. but i have yet to try this since using the pcv setup to see if it will actually work. just haven't taken the time to.


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