Rpm90001 Posted June 12, 2011 Share Posted June 12, 2011 Ok, ***I'm almost embarrassed to ask this question.. With 30 years working on cars an bikes this seems like something I should know..but anyways... I just finished doing head gaskets on my 00 legacy 2.5 also did the timing belt and all the rollers and tensioner. ***My question is ( hidding my face). While turning the motor over by hand on the engine stand, I put my hand over the exhaust port and there was a hell of a lot of vacuum created while turning the motor over, ***it would also puts a lot of air depending on where I was in the stroke. *** Is it normal to create any vacuum at the exhaust port? *** I'm near 99.9 percent sure I have the timing correct. ***I'm ready to drop this motor back in, but this has me a little confused. ***Someone put my mind at ease... Thanks for any help.. G Quote Link to comment Share on other sites More sharing options...
idosubaru Posted June 12, 2011 Share Posted June 12, 2011 if you did the heads right and the timing belt marks are dead on you have nothing to worry about. what you're describing is not a standardized test, i wouldn't worry about it. if the valves are slightly opened and the pistons are receding then maybe. which way are you turning it over by hand? did you try both ways? Quote Link to comment Share on other sites More sharing options...
obk25xt Posted June 12, 2011 Share Posted June 12, 2011 Were you turning it the correct direction? (I'm almost embarrased to ask that!) Quote Link to comment Share on other sites More sharing options...
Fairtax4me Posted June 12, 2011 Share Posted June 12, 2011 You know I've never bothered to see if the exhaust pulls any. When you set the crank did you use the notch on the reluctor tooth for timing? Did you have the cam sprockets off? You made sure the one with the notches on the back is on the drivers side head right? The notches are for the cam position sensor. Quote Link to comment Share on other sites More sharing options...
Rpm90001 Posted June 12, 2011 Author Share Posted June 12, 2011 Turning it over clockwise. It just sounded funny, that's why I put my hand over it. I just did not expect it to create any vacuum at the exhaust port Maby I'm just looking into this a bit much. Just did not seem right, but if something is wrong I want to correct it while it is on the stand Quote Link to comment Share on other sites More sharing options...
Rpm90001 Posted June 12, 2011 Author Share Posted June 12, 2011 (edited) By memory I used the colored dot on the crank gear, and the key on the crank was in the down position. I replaced the cam seals, but did them 1 at a time so I know I did not mix them up. Geo Edited June 12, 2011 by Rpm90001 Quote Link to comment Share on other sites More sharing options...
ocei77 Posted June 12, 2011 Share Posted June 12, 2011 Can't answer your vacuum question, but since this is your first Suby engine. Do a search on procedure for "burping" the coolant system. Suby's are not a fill and forget type of system O. Quote Link to comment Share on other sites More sharing options...
Rpm90001 Posted June 12, 2011 Author Share Posted June 12, 2011 O. Thank for the advice. Glad to see you here too! I want to put the motor in, but would like to hear someone say " yep that's normal". I think it's my OCD kicking in...I just can't let it go. Quote Link to comment Share on other sites More sharing options...
Fairtax4me Posted June 12, 2011 Share Posted June 12, 2011 As long as you used the notches, not the arrows, to time the cams you should be set. Quote Link to comment Share on other sites More sharing options...
GeneralDisorder Posted June 12, 2011 Share Posted June 12, 2011 Valve overlap will cause the intake valve to open before the exhaust valve closes and the piston will be traveling down on the intake stroke. When turned over slowely this wil result in a suction on the exhaust port for a moment - at operating speed the expanding hot exhaust gasses will help pull in more air/fuel mixture as they leave a vacuum in their wake upon exiting the exhaust port. So yes - that's normal. GD Quote Link to comment Share on other sites More sharing options...
MilesFox Posted June 12, 2011 Share Posted June 12, 2011 If you run the car with no header, it makes bloop-bloop noises and sounds almost like it is underwater. Quote Link to comment Share on other sites More sharing options...
1-3-2-4 Posted June 12, 2011 Share Posted June 12, 2011 I heard that's not good for the valves? having said that I've ran with just the headers on and boy is it loud.. I only did that to blow whatever was in the headers out.. lucky for me I get to do it all again in a few weeks. Quote Link to comment Share on other sites More sharing options...
Rpm90001 Posted June 12, 2011 Author Share Posted June 12, 2011 Thank you everyone. GD that is what I was hoping to hear. I know I had everything set correctly. Thanks again G Quote Link to comment Share on other sites More sharing options...
Crazyeights Posted June 18, 2011 Share Posted June 18, 2011 I can confirm it also. I oiled up an ER27 and taped off the ports for storage a couple years ago. I went to roll it over by hand and it tried to suck in the tape on the exhaust ports:grin: I forgot it was even there. Quote Link to comment Share on other sites More sharing options...
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