I just finished changing my head gasket (there was combustion gases coming up the radiator, #1 cylinder had coolant burned up inside, and the gasket looked pretty nasty..)

this is a d15b7

It started right up, but I noticed what I thought initially was an exhaust leak. There is a little bit of a fart/leak sound coming from the intake when I rev it, which threw me off, but then I noticed the air coming out of the dipstick between the exhaust manifold runners. It's not super strong, feels like if you blew gently in a sputter

Is this a positive crankcase ventilation thing? I remember that the PCV valve has a hose that goes down below the intake into this black box thing. It has a clip on the hose there holding it to a plastic thing, but when I was trying to remove the hose from the plastic thing, the whole assembly, plastic tube and all, came out of the black box (!). When I reassembled, it seemed to go in pretty tightly, so I didn't think much of it.

Also there is a bit of a rough sound with whine coming from the timing belt area. I can only hear it when revving -- is this normal for a new belt?

lastly, there is a tiny bit of white smoke emitted from the tailpipe on deceleration of the motor. The car is still up on stands, haven't driven it yet

TIA!

 

Something to add -- when I do the pinch check as suggested by the service manual (pinch the hose above the PCV) the engine speed drops a little, and comes back up when I release the pinch. The manual says to listen for a click from the valve, so I took a pvc pipe and aimed it at the valve and pinched -- sure enough, it clicks.

what could it be!

 

as for the rough sound I think it's from all of those belts (3! + timing belt) that Honda decided was necessary. I've just never paid attention before, but compared to a mazda that was nearby, it seems normal. was thinking I might have put on that concave plate, the one that goes over the timing belt drive pulley and before the crank pulley, backwards.

Would be nice if someone would chime in if they have accidentally done that before -- what was the effect of the plate going on backwards?

And on the air -- I guess maybe I just have some blowby, but it doesn't seem too bad. Seems that other people who have noticed this usually complain about the dipstick shooting out of the holder, but this isn't happening. Also the PCV valve and tubing has been taken out of the equation, as I removed the tube that outputs from the black box (what is this thing called anyway?) on the block. That resulted in no change.

Well, hopefully someone finds this thread informative in the future. I'll do a leak down test in a few days and report on it, for reference.

 

That plate guides your timing belt, keeping it from sliding off the crank sprocket. Putting it on backwards will have the sharp edge into the belt, which is going to damage it. Absolutely needs to be re-done immediately if that's the case.

Also overtightening the timing belt will cause it to make a whirring sort of noise, though a little of that noise is normal especially with a new belt. Be sure to follow the tightening instructions and use only force from the spring. Do not push on the tension roller to make it tighter.

Air pulsation in the crankcase is normal. Seems the PCV system is OK. If your piston rings are bad you will have more "air" trying to come out of the crankcase than normal. Normally there is a slight negative pressure, which can be observed by taking the oil cap off and holding a paper card over the hole. It should be sucked down, not blown up. Mostly with bad rings it will burn oil and make blue smoke from the tailpipe. There should be a rubber plug on the top of the dipstick to seal it in the tube.

You will see some "white smoke" until after you drive a little and get all of the water out of the exhaust system that got in there from the bad gasket.

 

hmm -- yes smoke has gone away -- drove 150 miles, got 42mpg (all highway). Pretty good!

For the timing belt, I first put on the belt with the tensioner bolt very loose. then I tightened it to 33ft-lb so that I could match the starting point in the factory manual for the tension adjustment section. THEN i followed the instructions, starting with loosening the bolt 180 degrees, then turning the crank clockwise 4-6 turns (and the belt ended up in a stable spot in the middle of the pulleys), then turned the crank counterclockwise 3 teeth, and then tightening the tensioner bolt to 33 ft-lb.

Is there any way to know for sure if the plate was put on backwards without taking it all back off? I'm 95% sure it is on correctly, but you know, it's sort of like when you second guess yourself about locking your house door when you've already gotten to your car. It was the third time I had done it due to first forgetting to put the upper timing belt cover on before putting the valve cover on, and then I had forgotten to put on the bracket that mounts to the block and to the side mount before putting the lower timing belt cover on (double doh!!).

Hmm, you think after 5-6 hours of engine time it would have snapped the belt by now, if it were on backwards? thx for your comments!

 

it occurred to me that I could simply remove the valve cover and then the upper timing belt cover to see if there was any wear on the belt. Will do this tomorrow!

 

Yes, you can check it just by removing the upper cover. Make sure the belt is running on the center of the pulley, and the outer edge is not damaged.