SkinnyMan

Ok, I have an 86 305 tpi with ~136k miles on it.

The car starts up with blue puff of smoke, and I’ve been told while driving there is a little bit of blue smoke coming out as well. I hate it when I see other cars driving with blue smoke puffing out so I can’t be doing it as well. I want it fixed.

As far as I know I shouldn't have any blow by problems.

I had called the local cylinder head shop, and they said that doing a valve job on my current heads would hurt the car. With the valves sealing completely it would cause more problems inside the motor.

As far as I know, more pressure inside the chamber shouldn't hurt anything.

I understand most of you guys here say working on a 305 is worthless well, a 350 is long on the way, and this is a temporary fix, for my problem I have at the moment.

So my question is, will getting a full valve job have any adverse effects on the motor?

Thanks.

meangene83

I have had high mileage engines start using oil badly after putting rebuilt heads on, I'm not sure why it happens but it does happen. My suggestion would be to leave the heads on and just put new valve seals in, it's a lot cheaper so you can get the 350 sooner

ede

for the cost and time involved compared to the gain i wouldn't take the heads off, i would replace valve seals.

SkinnyMan

feel like a dummy for asking.

how do you go about changing the valve seals?

Red Devil

Typically valve seals will only produce a puff at startup... unless they are really bad. Grab a repair manual and you'll not only have directions, you'll have another resource for the future as well.

Only way to know this is doing a compression test, at the least. I suggest you do that. If that's ok, then I'm with eded, just do the seals.

SkinnyMan

Ok, after I asked that question I searched for a while and read up on everything I could.

I know what tools to get now and the process. My only question is this, what type/material should I use?

I have been reading about umbrella and positive seal, and the differences.

Some people seem to think replacing the exhaust valve seal hurts the motor in the long run; I don’t want to cause any adverse effects. Is this true with your experience red devil and ede?

Also, as to my knowledge, the car smokes at startup, and when I sit at a light, and get going blue smoke comes, and at a drive through, when sitting for a while(running) she will smoke one more throttle is given. I've had people hit the pedal while I watched the tail pipes and I saw no smoke.

About 5 months back I had a problem with my timing chain, and a pushrod broke. One of the exhaust valves was not opening. Could that have caused major problems to the ring and caused continuing blow by problems?

I asked a friend, and he told me if smoke was coming from the valve covers while the car was on then there is blow by, but the degree in which/color comes out makes a large difference. When I take the oil cover off some white (steam like) cloud will come off then dissipate. If I watch the passenger side valve cover when the tube is disconnected, I may see a few white poufs but that is all.

I do not own a compression gauge, but I will ask my friend Brian if he could loan me his.

What are good figures for compression?


Thanks.

ede

i use the positive and o ring both, next heads i do for myself will have teflon seals