Smokin Hemi... Update.

Smokin Hemi... Update. - 06/05/14 03:44 AM

Alright guys I'm at my wits end. I have a blown 472 Hemi with alum. heads. This winter we pulled the motor for some external oil leaks. We noticed that the rockers were kinda beat up so I bought a set of rollers, replaced the cam and rebuilt the Demon Carbs. Now as soon as it warms up to temp it starts smoking (blue) out the tail pipes. More when I get on it or let up on it. Not as much when just cruising, but still smokes. I thought it was the intake gasket, just replaced that again, still smoking. I don't know where to look next.

Posted By: RapidRobert

Re: Smokin Hemi... - 06/05/14 04:56 AM

I'd have to say it's still the intake

. I dont think the valve seals went south or stem to guide clearance suddenly became too much. A possibility would be an oil ring fubared but k.i.s.s. the worsenening under increasing vac in hg points to the intake. The oil has to be getting sucked into the intake tract somehow. Post how it goes

Posted By: Cab_Burge

Re: Smokin Hemi... - 06/05/14 07:55 AM

Which brand of aluminum hemi heads are you using? When you took the motor apart to replace the lifters did you see oil in the intake ports or not? Oil comes into the combustion chamber several different ways, intake gaskets sucking oil, valve guides, rings or maybe sometimes from PCVs

I feel for you, I've fought that demon more than once, that is one of the reasons I commonally call them Hemiroids motors, they can be a big pain in the rear smetimes

BTW, all the problems are fixable, once you define the problem correctly

Posted By: DAYCLONA

Re: Smokin Hemi... - 06/05/14 12:03 PM

Are you pooling any oil inside the plug wells/tubes, oily plugs by chance?

Posted By: Xlr8us Rapidus

Re: Smokin Hemi... - 06/05/14 12:59 PM

The old intake didn't look bad, but replaced it with the Mr Gasket better one. If the valve seals were bad wouldn't it smoke at startup? They are Mopar heads. No PCV valve. Seems to be a little oil in the plug wells, but the #2 and #4 plug looked like they were "dipped" in oil! I did have the intake valves replaced also. Did not replace the seals, he told me they were good.

Thanks, Mark

Posted By: RUNCHARGER

Re: Smokin Hemi... - 06/05/14 04:34 PM

Are the studs into the heads sealed properly?

Sheldon

Posted By: DAYCLONA

Re: Smokin Hemi... - 06/05/14 06:13 PM

Quote:

The old intake didn't look bad, but replaced it with the Mr Gasket better one. If the valve seals were bad wouldn't it smoke at startup? They are Mopar heads. No PCV valve. Seems to be a little oil in the plug wells, but the #2 and #4 plug looked like they were "dipped" in oil! I did have the intake valves replaced also. Did not replace the seals, he told me they were good.

Thanks, Mark

Do you have the compression washers on the spark plugs? if so this very well may be your issue, if plugs currently or in the past were installed with the compression washers, the HEMI plug tube has been damaged/distorted and oil is entering the cylinder, seen it before, common mistake, if this is the cause, replace the tubes, and remove the compression washers from the spark plugs, the HEMI tube is your compression "washer"

Mike

Posted By: Xlr8us Rapidus

Re: Smokin Hemi... - 06/05/14 06:18 PM

Quote:

Are the studs into the heads sealed properly?

Sheldon

I used ARP thread sealant on all studs.

Posted By: Xlr8us Rapidus

Re: Smokin Hemi... - 06/05/14 06:20 PM

Quote:

Quote:

The old intake didn't look bad, but replaced it with the Mr Gasket better one. If the valve seals were bad wouldn't it smoke at startup? They are Mopar heads. No PCV valve. Seems to be a little oil in the plug wells, but the #2 and #4 plug looked like they were "dipped" in oil! I did have the intake valves replaced also. Did not replace the seals, he told me they were good.

Thanks, Mark

Do you have the compression washers on the spark plugs? if so this very well may be your issue, if plugs currently or in the past were installed with the compression washers, the HEMI plug tube has been damaged/distorted and oil is entering the cylinder, seen it before, common mistake, if this is the cause, replace the tubes, and remove the compression washers from the spark plugs, the HEMI tube is your compression "washer"

Mike

The washers were on there previously, not now.

Posted By: Xlr8us Rapidus

Re: Smokin Hemi... - 06/05/14 06:22 PM

Also, #4 plug looks snow white!

Posted By: 71birdJ68

Re: Smokin Hemi... - 06/05/14 06:28 PM

Could you all keep talking about this. My motor is smoking also. I have Stage V heads.

Posted By: Challenger 1

Re: Smokin Hemi... - 06/05/14 06:32 PM

Do a leak down test on the motor next if you haven't already. It's possible that your rings did not seat and you are blowing oil down your valve guides with boost. What kind of seals are you running?

I would run a PCV with properly baffled valve cover on the street with a blower.

Posted By: DAYCLONA

Re: Smokin Hemi... - 06/05/14 06:35 PM

Quote:

Quote:

Quote:

The old intake didn't look bad, but replaced it with the Mr Gasket better one. If the valve seals were bad wouldn't it smoke at startup? They are Mopar heads. No PCV valve. Seems to be a little oil in the plug wells, but the #2 and #4 plug looked like they were "dipped" in oil! I did have the intake valves replaced also. Did not replace the seals, he told me they were good.

Thanks, Mark

Do you have the compression washers on the spark plugs? if so this very well may be your issue, if plugs currently or in the past were installed with the compression washers, the HEMI plug tube has been damaged/distorted and oil is entering the cylinder, seen it before, common mistake, if this is the cause, replace the tubes, and remove the compression washers from the spark plugs, the HEMI tube is your compression "washer"

Mike

The washers were on there previously, not now.

Well chances are the tube bottoms are distorted by the compression washers being on the plugs, so I'd replace the tubes, don't bother trying to reshape the tube base, and install the plugs (new set) without the compression washers, fire it up, clean it out

and see if the smoking has stopped, I've seen this very issue over the decades on quite a few HEMIs, common mistake

Mike

Posted By: Xlr8us Rapidus

Re: Smokin Hemi... - 06/06/14 03:20 AM

Here's where I stand, I'm pretty sure it's not the intake gasket. Replaced it twice and it looked like it was sealing. With the blower and intake off, the top of #4 valve looks considerably cleaner than the others. I think this also rules out the spark plug tubes. That only leaves valve seal or head bolt. There doesn't seem to be any oil where the head bolt goes into the intake port. So I'm leaning toward valve seal. If I get the spring compressor from Mancini or Detroit City, how much of a pain is this to do with the heads on?

When does this car start to become fun?

Posted By: RapidRobert

Re: Smokin Hemi... - 06/06/14 03:36 AM

Quote:

When does this car start to become fun?

Sometimes walking away for 48 hrs works wonders. It'll likely restore the emotions back to a dead calm (or much closer to it) which is needed in the mechanic world. Mr Murphy can be tough to deal with

Posted By: Challenger 1

Re: Smokin Hemi... - 06/06/14 12:47 PM

Quote:

Here's where I stand, I'm pretty sure it's not the intake gasket. Replaced it twice and it looked like it was sealing. With the blower and intake off, the top of #4 valve looks considerably cleaner than the others. I think this also rules out the spark plug tubes. That only leaves valve seal or head bolt. There doesn't seem to be any oil where the head bolt goes into the intake port. So I'm leaning toward valve seal. If I get the spring compressor from Mancini or Detroit City, how much of a pain is this to do with the heads on?

When does this car start to become fun?

Once I took off all the race stuff off my street car, it became fun and way faster!. I know you can't do that with a blower very easy, but that's what I did 10 years ago with my 340 and have really enjoyed it in the last 10 years. It's not stock by any means, just close enough to be reliable and it runs really well with it's 10.5-1 KB pistons, single plane intake and Eddie heads.

Are going to do a leak down before taking anything apart this time, so you know whats wrong?

Posted By: Xlr8us Rapidus

Re: Smokin Hemi... - 06/06/14 05:36 PM

Quote:

Are going to do a leak down before taking anything apart this time, so you know whats wrong?

Prob will do a compression test this weekend. Valve seals are cheap enough, I just hate to spend $200 for the tool to compress the springs and find out that wasn't the problem.

Posted By: RapidRobert

Re: Smokin Hemi... - 06/06/14 06:07 PM

You might be able to rent one for cheap (an ad on CL could get a response). In addition not sure if a leakdown could pinpoint fubared oil rings or just the compression rings but I would seriously consider locating one/doing a leakdown before tearing it down

Posted By: Xlr8us Rapidus

Re: Smokin Hemi... - 06/06/14 07:09 PM

Thank you to everyone. I'll keep you informed.

Posted By: Challenger 1

Re: Smokin Hemi... - 06/06/14 07:48 PM

Quote:

Quote:

Are going to do a leak down before taking anything apart this time, so you know whats wrong?

Prob will do a compression test this weekend. Valve seals are cheap enough, I just hate to spend $200 for the tool to compress the springs and find out that wasn't the problem.

You need to do a leak down to learn any thing, different than compression test.

Spring compressor for use on the head can be fabricated pretty easy at home with no welder in some cases.

Who out there has made there own to post a picture of it. I have made a couple over the years but I used a welder.

Please post your pictures of your homemade compressor to help this guy out.

Posted By: Xlr8us Rapidus

Re: Smokin Hemi... - 06/08/14 01:44 AM

Did a leak down after warming engine and removing plug tubes. Only checked #1, 2 and 4. About the same results from all. 40% leakage... that don't sound good. Sounds like air under the blower.

Posted By: Xlr8us Rapidus

Re: Smokin Hemi... - 06/08/14 08:06 PM

Think I found the problem. #4 intake rocker is broken! Not sure why yet. These are a used set of Norris 1.7s.

[image]

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Posted By: Cab_Burge

Re: Smokin Hemi... - 06/09/14 01:21 AM

Quote:

Think I found the problem. #4 intake rocker is broken! Not sure why yet. These are a used set of Norris 1.7s.

[image][/image]

The broken intake rocker should make the motor miss, not smoke

The rocker is broken becuase of one of two reasons, it was defective or over worked, stressed, beyond its designed capabilities

I hope none of the others start breaking now

Posted By: Xlr8us Rapidus

Re: Smokin Hemi... - 06/09/14 12:35 PM

Quote:

The broken intake rocker should make the motor miss, not smoke

If the intake valve is not opening the piston is still pulling a vacuum, it's pulling oil past the rings and seals.

Posted By: JohnRR

Re: Smokin Hemi... - 06/09/14 03:57 PM

Quote:

Did a leak down after warming engine and removing plug tubes. Only checked #1, 2 and 4. About the same results from all. 40% leakage... that don't sound good. Sounds like air under the blower.

IF you found 40% leakage I think you found the problem ... and it's not a broken intake rocker ... if the air is not coming out the intake or the exhaust then that leaves the rings ...

Posted By: Challenger 1

Re: Smokin Hemi... - 06/09/14 04:12 PM

Quote:

Think I found the problem. #4 intake rocker is broken! Not sure why yet. These are a used set of Norris 1.7s.

[image][/image]

Blowers create boost as you know, but also put a incredible strain on the rockers, push rods and lifters, a lot of strain. So you need a good valve train, I have no idea about your rockers?

The broken rocker is not the reason for 40% leakage, I'm betting the rings didn't seat during break in usually because of the wrong fuel mixture during break in.

Good luck with it, did you build it?

Posted By: Xlr8us Rapidus

Re: Smokin Hemi... - 06/09/14 05:01 PM

I Did not build it. I bought it complete. I'm not sure on the accuracy of the leak down. It's a Harbor Freight piece. I think I found a replacement rocker.

Posted By: dogdays

Re: Smokin Hemi... - 06/09/14 05:52 PM

Norris rockers were a higher-end product of some years ago, maybe they're still being produced. IIRC they were investment cast stainless steel.

R.

Posted By: Xlr8us Rapidus

Re: Smokin Hemi... - 06/09/14 06:43 PM

I was told they're gone. Looking into some Stage V rockers now.

Posted By: Xlr8us Rapidus

Re: Smokin Hemi... - 06/29/14 02:53 PM

Replaced the broken rocker and all seems good. Just a bad rocker I guess! Thanks to everyone for the help.

Posted By: ScottSmith_Harms

Re: Smokin Hemi... - 06/29/14 03:05 PM

I had Dick Landy Industries build my S/S Hemis back in the 80's and I ran DLI roller rockers on my engines. One time while visiting the shop I asked Dick what he thought of Norris rockers, his reply was pretty straight and to the point.

"This has nothing to do with them being competitors of mine, if I were told my only choices were Norris or stock, I'd run stock rockers, Norris are junk, they break"