Valve stem seals info needed and is it worth while in my case?

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SirRobyn0

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good job, side play in valves tough fix without pulling heads, tube shims i dont mess with, knurl stems, shim guides, new valves,much more than that, pick heads you really want 1.98 In 76cc or less chambers ,port yourself. 50 to 75 ponies w/right cam....thats a rarity leak from intake,any idea what caused it... curious why change heads on crate engine? chevy crates are well match performance engines, shortblock way cheaper build than crate, LS or Gen I 350 even better, but thats my favs
I know there are a lot of posts, I think something got lost in translation. My truck has a 305 of unknown mileage. At one point I discussed and think talked the idea of replacing the heads, wiht reman heads. I think I also talked that my long term goal is to eventually put a 350 in it, which I was ready to do, but my builder was backed up. So all these pages are about what to do with the old unknown, but probably high mileage 305.

As for what caused the intake to leak and suck oil, other than age and time, I didn't see anything wrong on either the head side of the gasket or the intake. I agree that it's a rarity leak, and I'm still surprised there were no external vacuum leaks, but it is what it is and it's fixed now. She's actually running better than ever which makes me wonder how many years it leaked just a little....
 

Rusty Nail

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Made me wonder how many other trucks do. How many different threads in this msb can be attributed to the same thing..??
Thanks Robin for raising awareness.
We could make one of them ribbon stickers! Might even sell 2 or 3 lol.
 

84c10Tony

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What an ordeal, several years ago, tried the same thing with seals, about the same as what transpired here on my 84' 305.
Tried the bar, and the small wind down pinch type (forgot name), finally found out the shop at the college put in an older engine, 77' Caprice 305, sheesh. No wonder seals didn't fit.
Even when I first picked it up, it did not run right, (local college, no warranty)
And they would not call me back about the wrong year and type of engine etc. (CA has rules)
Still, I never got to the intake manifold gasket...dang
Too bad I did not have a clue, still don't lol.
Costs were 2x higher than a new long block trying to have the problems fixed...oops.
 

SirRobyn0

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What an ordeal, several years ago, tried the same thing with seals, about the same as what transpired here on my 84' 305.
Tried the bar, and the small wind down pinch type (forgot name), finally found out the shop at the college put in an older engine, 77' Caprice 305, sheesh. No wonder seals didn't fit.
Even when I first picked it up, it did not run right, (local college, no warranty)
And they would not call me back about the wrong year and type of engine etc. (CA has rules)
Still, I never got to the intake manifold gasket...dang
Too bad I did not have a clue, still don't lol.
Costs were 2x higher than a new long block trying to have the problems fixed...oops.
I'm sorry to hear about all the money spent on your motor. That was kind of my thing. I don't mind putting a little time and money into the 305, but eventually it'll get pulled for a 350. I get to a point in the year where I need the truck for the farm and don't have a lot of free time. Honestly I would not have spent as much time on that motor as I did if it weren't for the boys in Spokane being several months out on a 350.

I guess now the thing I have to decide is if I want to replace this engine this winter or continue to run it. Honestly it runs better now today than it had the prior 4 years and it did run good then too, it's dang near flawless now. I hate to throw that away, just because I want a little more oomph when I'm towing. My dog has a surgery coming up in the end of August, and sometime I need to decide if I'm putting a tranny in my 96 Grand Cherokee or what. Then I'll decide what happens this winter with the square.
 

84c10Tony

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Now that it runs well, (good job btw), logically, run it for a year or two till the dog is fixed up, the Cherokee is fixed up, the "do list" is fixed up (well...you already know).
Heck, you might just cruise a tad slower for a whole lot longer...frugally.
Enjoy the ride, we get only one, no returns or refunds.
 

SirRobyn0

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Now that it runs well, (good job btw), logically, run it for a year or two till the dog is fixed up, the Cherokee is fixed up, the "do list" is fixed up (well...you already know).
Heck, you might just cruise a tad slower for a whole lot longer...frugally.
Enjoy the ride, we get only one, no returns or refunds.
Thanks!

Oh yes, I enjoy the truck for sure. I really do not mind the 305, it's done each and everything I've asked it to. The truck has hauled or towed everything I've needed in weather from below freezing to 100F and though rain storms. Zero complaints really. Slow on hills? Yes, but really that's not a big deal she still gets the job done!
 

SirRobyn0

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Any update ?
Yea sure. I've mentioned it in other threads and I guess I just never got back to this one so thanks for bringing me back here I'd like to close the thread up. It's fixed.

#7 no longer fouls and eventually I went to the back to a colder plug. R45TS and CR43TS are the two ACDelco plugs recommended for the motor. It seemed to wanna ping a little with the 45's, and my last set of 43's I wasn't happy with so I went with the NGK equivalent. Without checking my maintenance book or pulling a plug I don't remember the number. But it's been great, no more fouling, though I don't perceive an oil consumption change. Much to your dismay Rusty, I also went back to running 15W40 deseil oil.

I'm getting close to my second oil change since the doing the manifold, well really third BC I dumped it after a short amount of time 100 miles or so. I've changed it once since then and I'm about 500 miles till the next one so I'm somewhere around 5,500 miles since changing the manifold. So I feel confident saying the fouling is fixed.

Back when I did this I thought that I might go ahead and replace the engine this winter. Unfortunately my transmission is now giving me trouble so I'll be having that rebuilt soon and that will be the big money spent on the truck this year.
 

SirRobyn0

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You dont draw any connection between hot plug pinging and using 15-40??

Curious.

:hmm::hmm:
Not really. The oil never seemed to matter, and it's not a pinging that occurs during normal driving, but for example if I'm towing or hauling and going over the pass or big hill with the foot to floor I'd get some pinging, really it's mild pinging but I don't like ping so the step down in plug temp seems to make the difference. When I was running 10W40 or 10W30 it didn't seem to change it vs the 15W40. Running premium does the trick to, but at our current gas prices I'd rather avoid it as much as possible.
 

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