i have a 93 accord with the f22. i have replaced at least 4 pan gaskets and it just keeps blowing them. i do it by the book every time (10 ft pounds of tourque etc.) i used the honda gasket with honda bond last time and it still blew it afer two to three days. can anyone help?

 

You may have excessive crankcase pressure. This might be caused by blocked PCV system; check inlet air, PCV hose, and PCV valve. Or could be excessive blowby due to piston ring wear or damaged rings.

good luck

 

could a cold air intake cause to much air to get in and increase crank case pressure? i have already checked the pcv system and it seems okay to me, but i just started it with the pcv valve out of the valve cover and it seems like there is alot of crank case pressure but im not really sure how much there is sposed to be.

 

At idle, there should be negative crankcase pressure (crankcase fumes pulled into PCV and intake manifold). If positive crankcase pressure, something's wrong w/ engine (hole in piston!).

good luck

 

So if I pull off the PCV valve at low idle, and there is a sputtering of air coming out the valve cover hole, then that is indicative of blow-by from worn rings/valves?

 

Get a vacuum gauge and measure vacuum level at idle. It should be 18-22 in hg. If much lower, something is wrong; low compression, vac leak, etc.

good luck

 

Wait -- are you talking about inside the engine block, or inside the intake manifold?

The intake manifold has plenty of vacuum ... all of the vacuum-operated accessories run off of it and there seems to be plenty of suction on that side of the tube. I was talking about the engine block side ...

 

Measure intake manifold vacuum at idle. This is what is available to cause filtered air from air intake duct to be pulled into engine to replace oil vapor/blowby that exits via the PCV valve. If the intake manifold vacuum is low or positive (no vacuum), the air flow from crankcase to intake into engine. This can result in significant oil consumption and oily air intake duct and throttle body.

It is possible but difficult to measure crankcase pressure directly. You will need to tee the PCV outlet or inlet hose to connect a vacuum gauge.

Note, crankcase pressure will go positive when throttle is opened significantly and reverse flow occurs. Some reverse flow is normal and unavoidable. Excess or constant reverse flow is not. However, I'm not aware of any specs for idle vacuum but range of 19-22 in hg is typical for most cars.

One test I've seen is to place a piece of stiff paper over the oil fill inlet w/ engine idling. It should be pulled tightly down. If it is pushed off, then something is wrong.

good luck

 

I just checked the oil filler pressure ... there's definitely a lot of positive air pressure in the crankcase pushing the paper away from the hole. It makes a nice 10-20 Hz "put put" sound as if blowby from worn rings. However the air looks to be completely clear.

I'll have to double-check it again and do some of the other vacuum tests you mention. I bought a Mityvac a while back so I should have what I need to do the tests.

Deferring the oil pan gasket replacement for now ...

** update **

I drove the car around with the ODB2 reader attached ...

* First of all, I noticed that, with my normal accelerations I was never moving the throttle past 30 percent. Our other cars are 2005+ MY and all have electronic throttle ... I didn't realize how much resistance there is on a traditional cable throttle, and they there was a whole other level of acceleration I could get with the car! Whereas before I never brought it up much past 3500 rpms, I did a few hard accelerations and got the engine up to 5500 or so a few times. I'm not inclined to do it that often as it's an old engine. But no adverse side effects, no codes, smoke, roughness, etc.

* The transmission also shifts at a very low rpm -- seems like 3k or below. Is there a way to raise the shift points on these trannies?

* MAP on my reader shows the HG scale. At idle it was in the 6-8 range, and under hard acceleration it went up in the high 20s. Mostly on the highway it was in the ~15 area. Seeing as how regular sea level HG is 29, am I seeing the correct range for a non-compressor engine?

* still a lot of air puffing out from either the PCV hole or oil filler hole on the valve cover. So I suspect tired rings/valves.

* Also, when I turn off the engine after it's fully warmed up, and open the oil filler cap, I get the slightest wisp of smoke coming out of the valve cover. Is this normal?

* I checked the PCV valve ... lots of suction from the bottom of the PCV valve when I pull it off the valve cover. I replaced it a year ago an have never been able to hear it or the previous ones "click" ... but the suction tells me it's working. However it seems like it would not be able to suck all of the air coming out of the valve cover. Any suggestions here? if this air pressure is reponsible for the bulk of the oil pan gasket leaks, I'm wondering if replacing the gasket is really going to stop the leaking.

* So back to the oil pan gasket -- based on the above observations, should I hondabond the entire gasket top and bottom to get the best seal possible to hold in the pressure? Or will I still be fine with using Hondabond on just the special areas of the gasket?

Thanks. John

 

*** UPDATE ***

Just did a compression check: 165-165-165-165

For an engine with 245k miles on it, I was pleasantly surprised. I believe the factory spec is 178, with a minimum of 135.

Still looking for the source of the air pressure coming from the crankcase, and to understand if that would be a source of continued leaking once I replace the oil pan gasket.