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Distributor question

Phil513

Phil513

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I haven't worked on engines in years, so forgive the stoopid.

I need to get the heads rebuilt on my TBI 350.

Is there anything I need to know before pulling the distributor out so I can be sure everything goes back in the right place? Do I really need to get the engine to TDC first, or can I kinda put marks on stuff as I take it out so it goes back in right?

I just don't want to get hung up on some detail, as I'm doing this at my work, and if it sits there a long time I'll hear some bitching. lol.

Thanks.
 
Pull it. Put it to TDC with the heads off. When heads go back on if the valves are closed you are on TDC compression. If a valve is open you are 180 out.
 
do your head work. install heads, valvetrain..adjust valves... install intake.. rotate crank till #1 intake opens, than closes.. once closed, keep rotating till the timing marker reaches zero on the timing tab.. this is top dead center.. drop dizzy with rotor pointed at #1 cylinder...
 
Thanks guys, I think I get the gist. I probably worry too much.
 
Are you going to go vortec, do you already have aftermarket/worked heads that you are rebuilding or just stock?

Sorry, not that any of that matters to the original question you posted...
 
Carcinogen said:
Are you going to go vortec, do you already have aftermarket/worked heads that you are rebuilding or just stock?

Sorry, not that any of that matters to the original question you posted...
Click to expand...

No worries! No, just the stock 350. It runs good, and hardly burns oil, but makes an embarrassing big puff of smoke after it sits for a couple hours, I figure the valve guides are in a bad way. It doesn't seem to have any other issues, I'm just tired of the frowns.
 
it's seals... technically, you could do it with the heads on for a quickie....
 
set timming on tbi equipped vehicle is 1 wire weather pack plug over by wiper motor on firewall . unplug it and set timming . then turn off and plug back in .

set to zero .
 
ryoken said:
it's seals... technically, you could do it with the heads on for a quickie....
Click to expand...

Know what, the more I read, thats the way I'm going to go. Thank you! I think I can handle it, it's not so scary.

I am curious though. There are two seals, one down around the boss in the head, and a little O ring up on the stem underneath the keepers.

What the heck is that O ring sealing? It seems to just be sitting on the stem under the spring. I don't get it.

But that's what I'm gonna do. This turned from surgery into outpatient. lol.
 
I dont know about newer engines like the LS ones,but old small and big blocks used an o-ring on the valve stem factory--it will "seal" some against the guide when the valve gets pushed open,but mostly it just directs oil flow away from the stem so it wont flood it and get sucked in and burned..

There were other types of valve stem seals invented and used on many V-8's--there was a brand named "Toke" that made little green umbrella shaped seals that were like some GM used on other engines like Olds and Pontiac,that many auto machine shops would install in place of the original O ring ones,they fit around the valve guide and made a much better seal--some liked to use both these and the original O rings,but that sometimes led to the guides not getting enough oil and valves sticking,or the guides getting hogged out in short order..

For awhile Dorman had a kit out you could buy,that supposedly stopped the smoking from bad valve stem seals--all you had to do was remove the valve cover,the rocker arms,clean off the valve spring retainer with solvent and a wire brush,and "glue" their new seals right to the spring retainer--no dissasembly of the valve spring retainer,and chances of dropping a valve in the combustion chamber--not sure if it panned out well,or if they still have such a kit today..

I trust using nylon or poly rope stuffed in the spark plug hole with the piston at bottom dead center ,then turn the engine by hand slowly till you feel the piston crush the rope ,to hold both valves shut,more than using compressed air to hold them shut--I've have that method let the valves drop more than once,its hard to keep the air from trying to push the piston back down..or one "bump" against the valve and it can drop into the combustion chamber--then you get to pull the heads off..:(..but that might not be a bad idea,since the head gaskets might be about due,by the time valve stem seals fail,and some valves might need lapping or grinding too..

You can wrap a rubber band around the valve stem to help keep a valve from dropping too far in to be pulled back up...but I like using rope,there is no worries that way of losing one..
 
diesel4me said:
I dont know about newer engines like the LS ones,but old small and big blocks used an o-ring on the valve stem factory--it will "seal" some against the guide when the valve gets pushed open,but mostly it just directs oil flow away from the stem so it wont flood it and get sucked in and burned..

There were other types of valve stem seals invented and used on many V-8's--there was a brand named "Toke" that made little green umbrella shaped seals that were like some GM used on other engines like Olds and Pontiac,that many auto machine shops would install in place of the original O ring ones,they fit around the valve guide and made a much better seal--some liked to use both these and the original O rings,but that sometimes led to the guides not getting enough oil and valves sticking,or the guides getting hogged out in short order..

For awhile Dorman had a kit out you could buy,that supposedly stopped the smoking from bad valve stem seals--all you had to do was remove the valve cover,the rocker arms,clean off the valve spring retainer with solvent and a wire brush,and "glue" their new seals right to the spring retainer--no dissasembly of the valve spring retainer,and chances of dropping a valve in the combustion chamber--not sure if it panned out well,or if they still have such a kit today..

I trust using nylon or poly rope stuffed in the spark plug hole with the piston at bottom dead center ,then turn the engine by hand slowly till you feel the piston crush the rope ,to hold both valves shut,more than using compressed air to hold them shut--I've have that method let the valves drop more than once,its hard to keep the air from trying to push the piston back down..or one "bump" against the valve and it can drop into the combustion chamber--then you get to pull the heads off..:(..but that might not be a bad idea,since the head gaskets might be about due,by the time valve stem seals fail,and some valves might need lapping or grinding too..

You can wrap a rubber band around the valve stem to help keep a valve from dropping too far in to be pulled back up...but I like using rope,there is no worries that way of losing one..
Click to expand...

Thank you, thats some good info. I have read about both air and rope, rope sounds a little safer.

Oh, and the Fel Pro kits I have looked at come with both the umbrella style and the oring both. I'll have to think about whether to use one or the other, or both. Eventually I'd like to get a crate engine, so this is just kicking the can down the road a bit.
 
It's up to you. Personally, with the amount of time invested in trying to keep valves up and rotating the engine, I would probably take the opportunity to pull the heads, put on some fresh gaskets, and take a look at the pistons/cylinder walls. Head jobs are pretty easy on these motors. Then again my truck is lifted and I really don't feel like bending over the hood changing 16 valve seals...:D
 
paratrooper307 said:
It's up to you. Personally, with the amount of time invested in trying to keep valves up and rotating the engine, I would probably take the opportunity to pull the heads, put on some fresh gaskets, and take a look at the pistons/cylinder walls. Head jobs are pretty easy on these motors. Then again my truck is lifted and I really don't feel like bending over the hood changing 16 valve seals...:D
Click to expand...

Oh, I'll need a stepladder for sure. Better now than after I paint the fenders.
 
I'm 5-11. So even tippy toes wont work. lol. But hey, I have a few NFL bets for tomorrow, maybe I can skip the whole mess and go straight to a 6.0. hahahahaha. (That's not going to happen.)

 
Im also 5'11" and doing a vortec swap at them moment. I just removed the fenders, not about to mess around with it(although I also considered pulling the whole motor...)
 
Carcinogen said:
Im also 5'11" and doing a vortec swap at them moment. I just removed the fenders, not about to mess around with it(although I also considered pulling the whole motor...)
Click to expand...

Just curious, is there a compression ratio issue going to the vortec heads? I thought I read that somewhere.
 
There should be a slight compression increase going from a 76cc chamber to a 64cc on the vortecs. Depending on actual measurements(which I haven't taken...) it should put the compression ratio right around 9.5:1
 
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