Thread: 327 bad rings? has new heads!

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Originally posted by dutchhotrod
Hi Mike.

I am intersted in a compression test. I've never done one before. How do I accomplish this test? Thanks,

Jerry

thanks denny, dutchhotrod, go to the address denny just gave you that's tells you everything you need to know, better than i could.

Before you get carried away lets do a more detailed inspection...

1st) pull all spark plugs....do you have oil on all of them or just a few?

Do some of them have more oil on them than others...if so locate the cylinder with the most oil on the plug...

If you have oil on all 8 plugs it would be safe to say incorrect pcv ventalation....

If you only have oil on half of them are they on the same intake runner tract ....or seperate?

Pull the carb and look in the intake and look where the oil is tracking....

If you suspect the pcv run a Q-tip in the hose at the base of the carb and see how much oil gets on the Q-tip....

**Also if you are running an AutoMatic trans do the Q-tip test on the hose from the modulator valve.....( blown M valve will suck tranny fluid into the engine too)

Usually if it's a intake gasket you will get oil in 2 adjoining cylinders (1-3) (5-7) (2-4) (6-8) sbc ...If you are getting oil in more cylinder the pcv is usually the culprit...

If you are using the pcv valve you will also have to put a vent in the opposite valve cover....too much negative pressure and you never know which way the oil will go....most of the time right out the exhaust....

sure but you have to cover all simple bases first....why tear an engine down if you don't have too!

We do not know all about the hone job... how tight was it initially? how long did whoever hone each cylinder....it only take 45 seconds to cross hatch enough to get a semi-good seal

I would note if it was re-ringed and never fired they may not have seated...In that case run the engine 20-30 minutes above 2500rpm oscilating between 2500 and 3500 (build some heat in the thing) seat them in or take it out on the high way and abuse it for 50 miles....just keep the oil filled

Break it in like you want it to run....

Originally posted by dr_bowtie
sure but you have to cover all simple bases first....why tear an engine down if you don't have too!

We do not know all about the hone job... how tight was it initially? how long did whoever hone each cylinder....it only take 45 seconds to cross hatch enough to get a semi-good seal

I would note if it was re-ringed and never fired they may not have seated...In that case run the engine 20-30 minutes above 2500rpm oscilating between 2500 and 3500 (build some heat in the thing) seat them in or take it out on the high way and abuse it for 50 miles....just keep the oil filled

Break it in like you want it to run....

all ive told him to do is check comp. thats a long way from tearing a motor down.

I have built engines that have went 200,000 with no cylinder taper and minimal wear...I specialize in small blocks....How I do this is a trade secret....

But Yes a compression test would be one of the basic test...

He said only 4000 miles on the bottom end before re-ringing,,,what we dont know is what that initial 4000 miles was like.
As it has been said before,,,,get it out on the highway and try seat those rings.
Doing a compression check with unseated rings is gonna be hard to get proper readings.
Has been sitting for ten years,,,,was it ever run after the rings were intstalled??
Are the valve seal's now dried out???
He needs a good mechanic to be with him and walk him through the proper check's.
He's had really good advice from you guy's,,,now it's up to him.

After 10 years of sitting once he gets it running "right" he's probably gonna be replacing a lot of stuff. I had a tranny, was fine when I pulled it. Sat for about 2 years and now it won't hold third.

I'll second that.....

Thats whatI read about the 4000 miles.... they just may need to be seated....I have encountered this before on pieces some one else has done.....

I am a firm believer if you do it right it will live forever....I still run the same 283 I did in back in 88' the only thing ever done since then was different heads 8 years ago....I have logged 2500 passes (1/4) mile and still runs like a champ....

have the tranny chemically flushed and refilled that usually does it...

Cool my daily Astro with a 4.3 has 188,463 and running strong....crap for pressure though

I still plan to do a comp. check.

To clarify some of the questions brought up... the "new" rings have the 4000 miles on them that I mentioned. I know they had seated , because during the break in time and after, there was no smoke .
The honing was done with a drill, thinking back to it. I ran the motor for some time up to the 4000 mi. mentioned. THEN it sat for those 10 years. As soon as I ru na comp. check, I will inform ya'll of the numbers. If they are bad, it's going to be a new 350 short block. Thanks to all,

Jerry

rings could be stuck in the ring lands or just need to be re seated...how long have you run it ...smoking?

Dr. Bowtie and Denny:

I have run this engine off and on before the new heads for maybe 100 miles only since the 10 year sitting period. Then it sat for at least 3-4 months with out being turned over. Recently, I thought of reviving it, it smoked bad ,so I put the new heads on and now its smokes quite a bit. Since the new heads, I have run it around the block a few times with the smoke.

Originally posted by dutchhotrod
Dr. Bowtie and Denny:

I have run this engine off and on before the new heads for maybe 100 miles only since the 10 year sitting period. Then it sat for at least 3-4 months with out being turned over. Recently, I thought of reviving it, it smoked bad ,so I put the new heads on and now its smokes quite a bit. Since the new heads, I have run it around the block a few times with the smoke.

dutchhotrod, sometimes when you put new heads on old rings that makes the old rings worse, or in some cases make a motor use oil that wasn't using oil in the first place. the new heads put more pressure on the old rings, so this might explain the extra smoke. it could be a lot of things but checking the comp. wet/ dry will tell what you have inside your motor and you can stop guessing and it don't cost anything but a little time. if the rings checks ok then you can go on to something else. if the rings check bad then you can fix then. this i how you check to see what shape your rings and block is in. it should be done every now and then anyway. why this thread had to get all out of shape is beyond me. from what you told us in you first post there was nothing else to do that made any sense to me, but to check the block and rings. there is a reason warrantees has a mileage and time limits and that's because setting does as much harm to parts as running them or worse in some cases. 10 yrs of setting is bad on rings, might help seal a intake gasket though. i try to base my answers on a good possess of elimination based on yrs of experience not something that happened few times a couple yrs ago. before i closed my shop up in Richmond 1995 my brother had a motor rebuild plant down in NC and from late 92 until 95 we installed right at 1300 motors at 3 dif. locations in Richmond and the standing order was no motor job left the shop unless i checked it off, and every come back i personally watched the tear down and wrote a report of my findings to the motor plant in NC, now that's a lot of over bored blocks, broke rings, bad valve guides, and a whole lot of blown head and intake gaskets. we were well trained on the proper way to install the motors and how to diagnose a problem when it came back, so i don't base my findings on a couple of anything. i hope its not the rings but you gotta check them. finding a intake gasket blown on the bottom side of a intake is one of the hardest things you can do on a motor and most of the time you cant see the problem after you pull the intake so that's normally the last thing you do when you cant find anything else, but you can know for sure about the rings.as far as the breathing go, breather caps work just fine, but you have to block off the pcv valve vac. hose. a stopped up pcv valve dont cause a motor to smoke, it builds up pressure in the pan and the pressure has to go somewhere so it blows out the weakest gasket on the motor all you need to do is get the pressure out of the pan. i dont know what kind of trans you got but if its automat. then you might be sucking trans. fluid out of the trans into the motor, but thats another story depending on what you find with the rings. white smoke at the tail pipe can be motor oil, trans. fluid or brake fluid,

Originally posted by csf03716
first off this thread has not gotten "out of hand" there have been quite a few very very good smart intelligent people giving excellant advice.......it is ultimatly up to dutch to proceed forward....and im sorry But if a cranck case becomes pressurized, oil will act like water and seek the path of least resistance...it will get sucked down valve guides and ultimatly cause SMOKE! as well as plug fouling...and will throw off the air/fuel mixture settings at the carb...you cannot and should not ever doubt what might cause anything to happen............and MY experience is based on 20plus years of high pressure steam and gas powerplant generation so lets not let this get outta hand and have a big pissin contest ..........

quote 327 with only 4000 mi on bottom end. 0.40 pistons, was honed and re ringed by a friend 10 years ago and sat a long time.Professionally built heads with positive oil seals/ 2.02/ 1.6 valves , bronze guides. Brand new Edelbrock 600 cfm manual choke carb on torker intake. No vaccum leaks. idles very smooth after setting the air/fuel idle screws as directed. unilite dist.

if you can take that information and come up with a stopped up pvc valve or a blown intake gasket then thats fine. i cant. with a stopped up pcv valve the pan pressure is gonna go the path of least restance and that will be a gasket somewhere, not pass the new valve seals. if oil could get passed the valve seals that easy then it wouldnt hold any oil back at anytime. it dont take but a little pressure in the pan before it will blow a gasket. 99.99 % of the time your not gonna be able to adj out any kind of vac leak (with the idle screws)must less one thats sucking oil into the cylinder. if the pcv valve was stuck "open" it will suck oil into the cylender, but he said he had checked that.