Mid Century Cadillacs

General Category => Mid Century Cadillac Discussion => Topic started by: JAG56Cad on July 22, 2018, 10:44:09 AM

Title: Back to my smoking issue >:(
Post by: JAG56Cad on July 22, 2018, 10:44:09 AM
Well had a chance to take the left back pistons out yesterday and today and I believe I may have found my issue with the foul plugs and smoke out from the tail pipes. http://midcenturycadillacs.com/index.php?topic=3938.msg23296#msg23296

I had a feeling my problem lie with the piston(s) somehow, my last compression test reading was about 150 on all except for #6 having about 130.   ???

I removed #5 yesterday and was not happy with what I saw, both compression rings 1 and 2 were clocked about 30 degrees and the top and bottom oil ring were also about the same about 90 degrees from the compression one. The attach picture is #3 which I removed today #1 and #7 had similar ring layout.   :o

Second I removed both compression rings and found the ring gap was above the normal range of 0.013 - 0.023 both were on the range of 0.027-0.028.    >:(  The cylinders and pistons are bore 0.020 over (that is what is stamped on the pistons) so I have a new set coming by end of the week.

Now Im not an expert but I would take a while guess the rings would need to be properly clock on the pistons and from my research the top and bottom compression should be at least 180 degrees from each other. The oil ring would also need to properly place and gap set at least with all gap away from the piston pin. 

Oh well as Johnny says this is just a hobby..!, but not a fun one when temps around here are in the 100 plus.   :'(
Title: Re: Back to my smoking issue >:(
Post by: novetti on July 22, 2018, 07:35:03 PM
Piston skirt looks pretty good from here. Are these new pistons?

How is your valve guides / Valve stem clearance? Smoking could be from excess oil coming from there.
Title: Re: Back to my smoking issue >:(
Post by: Roger Zimmermann on July 23, 2018, 02:09:41 AM
On my '56 de Ville, I had heavy smoke from time to time after I overhauled the engine. I also removed all pistons to see if something was broken, nothing bad, and still smoke after reassembly. Finally, it was the valve for the vacuum line at the vacuum pump inside the engine which was not good. Did you check yours?
Title: Re: Back to my smoking issue >:(
Post by: JAG56Cad on July 23, 2018, 08:41:03 AM
@novetti

The pistons are relative new they may have about 100 hrs of run time on them since I got the engine rebuilt back in 2008. Had not got the car on the road as I was doing other restoration inside, paint, etc. after the engine was done.

The current heads are the spare ones I got way back since my original ones were both cracked, standard for early 56. These ones were just clean and the bottom milled at the shop but the shop closed down so I grinded by hand before reassembly with same valves and springs.

I do intent to take them to a shop and have them go over and verify everything beforehand.   ;)

The issue of smoking was also present when I had the 390 (60 if I remember) fully rebuilt and installed. I did not have the correct rocker shaft for the 390 (used the same 56 rockers set) when I first tested the engine, so took them off and replace them with the spare 365 set. I do have a 390 rocker sets now that I could place with the 390 heads as well as the lifters and push rods as an alternative.

@Roger

Thanks, that was my first thought although the valve is/was fine I did blocked the line going up to the firewall vacuum manifold, just in case.


I still need to get the right side head off to get the pistons out on that side. Maybe taking one bolt at a time with our expected weather again in the high 100.  :(
Title: Re: Back to my smoking issue >:(
Post by: PHIL WHYTE CLC 14192 on July 23, 2018, 03:55:00 PM
I was going to say the same - the pistons look great! Valve stem seals, the vacuum valve etc are the usual culprits. Measure the bores just to check before putting it all back together. I had a friend who rebuilt the engine in his Triumph motorcycle, but only did the rings because the pistons looked great only to find that the pistons were standard and it had been bored out +20!. Phil
Title: Re: Back to my smoking issue >:(
Post by: JAG56Cad on July 23, 2018, 06:05:03 PM
I was going to say the same - the pistons look great! Valve stem seals, the vacuum valve etc are the usual culprits. Measure the bores just to check before putting it all back together. I had a friend who rebuilt the engine in his Triumph motorcycle, but only did the rings because the pistons looked great only to find that the pistons were standard and it had been bored out +20!. Phil

I have the rubber cups seals that mount in the valve guide instead of the O rings that came with the gasket kit, did not want to take a chance.  ;)

Thanks for the 411..!
Title: Re: Back to my smoking issue >:(
Post by: walt c on July 27, 2018, 03:26:07 PM
jose,
  After I rebuilt my 1955 331 it took forever to "breakin". I "used" quite a bit of oil for many miles. I also had smoke out of my downdraft tube and EVEN noisy rockers! (clicking constantly,sounded like solid lifters) A friend suggested I add some Lucas oil additive. I did and my oil consumption went from a quart every 500 miles to less then a quart after 1200 miles! Then my rocker became quiet and all is well. (50K miles since overhaul) A point of mention is that my oil pump pickup tube to oil pump did not have a gasket. (felt) Thanks to Roger Zimmerman I installed one and life is good.....feel like drinking a glass of wine like Johnny does. (by the way, sure was fun out last night in it feeling the factory air and my wife at my side)....walt...tulsa,ok
Title: Re: Back to my smoking issue >:(
Post by: JAG56Cad on July 27, 2018, 05:05:03 PM
@Walt,

Thanks for the 411..!

I just got back from the garage had to take a quick shower as I was totally drench, TX weather.   :(

I removed the right side head over the week and tackle the pistons today, same scenario as the left side they all had the compression rings facing down and both gaps about 20-30 degrees apart and were really gunky.  :o

I got a new set of rings yesterday and after a quick check by overlay them (old and new) it was obvious the machine shop cut (gapped) them way above the max tolerance.

I know they would need to be grind to the correct size, so that would be a project for tomorrow. Not sure how many will I be able to get done, but Ill take my sweet time for sure. Now as for the Johnny special relaxation elixir (aka wine) that would be after the task at hand, just need for Johnny to share his secret brand.  ;D

More updates forthcoming as I progress.   ;)
Title: Re: Back to my smoking issue >:(
Post by: PHIL WHYTE CLC 14192 on July 28, 2018, 02:22:54 AM
@walt c sounds like that was a great night out my friend. My car is non a.c. and we have had the hottest summer here for 42 years! Phil
Title: Re: Back to my smoking issue >:(
Post by: walt c on July 28, 2018, 02:51:43 PM
jose,
  Your comment "I got a new set of rings yesterday and after a quick check by overlay them (old and new) it was obvious the machine shop cut (gapped) them way above the max tolerance.

I know they would need to be grind to the correct size, so that would be a project for tomorrow"......well, I used to spent 8hrs on a ring set for perfect fit! Racing motors, but I fit my Cadillac 331 rings perfectly also....walt...tulsa,ok
Title: Re: Back to my smoking issue >:(
Post by: JAG56Cad on July 29, 2018, 08:04:17 AM
@walt c


Wellll... it seems the ring goods were good to me.

I checked one set on each piston and the top ones were within 0.018 gap and the second within 0.021 average no grinding was needed, so this set was a perfect fit.   :)

I took pictures of the old (top one) and the new (bottom one) which I overlay them so you can see the differences. P07290077 left side are the second ring and the right ones are the top rings.you can see the huge differences on the other pictures.   :o


As Johnny Im glad this just a hobby..!   ;)

More to come..!
Title: Re: Back to my smoking issue >:(
Post by: JAG56Cad on July 31, 2018, 09:56:50 AM
Well Im ready to install the new rings but I would need a set of new eyes and a fresh brain since mine is already running low.    :P

The push rod bearing from my view do not look good; not sure if they should be smooth or if these marks are normal wear, the crank shaft is perfectly smooth?

I did a quick caliper checked on the rods and the crank locations and all have the same diameter, the ones now on the rods are 0.010. I will check them with the plasticgage to verify.

Not sure if it is a waste of time doing the plastigage the way these bearing are of I should go for a new set?   ???
Title: Re: Back to my smoking issue >:(
Post by: Roger Zimmermann on July 31, 2018, 10:04:55 AM
I would get a new set and ask me what did the scratches?
Title: Re: Back to my smoking issue >:(
Post by: JAG56Cad on July 31, 2018, 02:20:10 PM
I would get a new set and ask me what did the scratches?

Roger,

Thanks for the feedback..!

Yes, my gut feeling was telling me to replace them since Im already dealing with the rings. I just drop the order so I hope this will get me back on track.
Title: Re: Back to my smoking issue >:(
Post by: russ austin on July 31, 2018, 06:50:50 PM
Did you prime the oil system before you cranked the car over for the first time?
Title: Re: Back to my smoking issue >:(
Post by: JAG56Cad on July 31, 2018, 07:59:28 PM
Did you prime the oil system before you cranked the car over for the first time?

Russ,

Yes I did prime the oil pump before hand to get oil pressure and circulation before hand cranking and several times before using the starter.

What got me puzzle is the main journals are all in great shape and shinning no scratches that I felt or notice.  ???

I will make sure this time in applying assembly lube on all these areas before hand, do not want to go over this in the future.  ;)
Title: Re: Back to my smoking issue >:(
Post by: novetti on July 31, 2018, 09:52:13 PM
If the crank journals were ground, with the new bearings the bearing clerance might be tighter than it should be.

Plastigague and confirm the current clearancing.
Title: Re: Back to my smoking issue >:(
Post by: rare eldorado on August 01, 2018, 08:28:21 AM
If there is a machine shop near you have them check the crank on their lathe .That would be no dought about the condition of the crank.They would be able to tell you what size and bearings too use.
Title: Re: Back to my smoking issue >:(
Post by: JAG56Cad on August 01, 2018, 09:39:14 AM
@novetti

That is one item that Im not 100% sure if the previous machine shop had done, I do not believe but. ???

@rare eldorado

Yes there is one which Im planning on taking the heads to be checked.

Taking the crankshaft would be a pain since the block still on the car.  :(

As I mention I did a quick caliper measurement and the journals and push rods w/the current bearings and both measure 22.37 (push rod caps were not fully torque just tight), the current bearings are 0.010. I will try the plasticgage with the new set coming this week to get a more accurate reading.

Fingers cross..!   ;)
Title: Re: Back to my smoking issue >:(
Post by: rare eldorado on August 01, 2018, 02:05:21 PM
jag56  plasticgauge will not tell you of the trueness of the journels just the clearance  .If they are slightly out of round bearings will not seat correctly Roundness is also from side to side on each journel not only circumference.This will affect your oil pressure.Each one may have to be turned and resized for new bearings.,An out of round journel can wear a bearing prematurely and cause a slight knock.It might be to your advantage to remove the motor and take out the crank.Worn mains can also cause a problem..also the thrust bearing wear .Taking the time too do this now might just save you a lot of money and problems later on.Donot forget too use a new oil pump.Also check the cooling chambers in the block if they are dirty or clogged it can cause the motor to run too hot and ruin your new rings.It might have to be boiled out to clean it.That is if the motor had not been redone early on.
Title: Re: Back to my smoking issue >:(
Post by: novetti on August 01, 2018, 06:39:40 PM
With the engine still in the car I would plastiguage 2 journals just to have an idea.

Read this

https://www.mahle-aftermarket.com/media/local-media-north-america/pdfs/cl77-1-205r.pdf

The machine shop if not familiar with these dinossaur cars might have left the journal dimensions bigger than they should be for 0.0025 - 0.003 that this engine requires.

Another question : What oil did you use? 20W50 ?
Title: Re: Back to my smoking issue >:(
Post by: rare eldorado on August 04, 2018, 07:12:04 AM
If that machine shop is not familiar with the older cars (witch does not make sense if he is any kind of machinist) you need to find one that knows what there doing .Mistakes can cost a lot of money and time.Agood machine shop has all the equipment    to do motor work of all kinds.All motors old and new are very much the same except for specs and there are books for that.
Title: Re: Back to my smoking issue >:(
Post by: PHIL WHYTE CLC 14192 on August 06, 2018, 02:48:16 AM
The machine shop I use over here in the UK has books of specifications of all cars going back many years. He had the info on my 331. I guess the modern cars are on line now.
Title: Re: Back to my smoking issue >:(
Post by: JAG56Cad on August 06, 2018, 09:03:40 AM
Sorry folks got held up with other projects/fires..!   >:(

Again thanks for all your input and details on this thread really good feedback.

Had a chance to polished the rod journals with 600/800/1000 grid wet just going slightly over them. I check the clearance and all were within specs between 0.002 and 0.003 with the new bearings, Service Manual states above 0.0045 would require to replace the bearings.
I did a quick check on the main journal bearings and the two center one were perfect. I check them with plasticgage and were within tolerance, Ive also slightly hone the cylinders.

Ive decided to clock the ring gaps at 180 degree between top and second compression as well as the oil rings with a 90 degree separation between them and 45 degree from the center pin. The black marks on the pistons are the guide Ive used to get them aligned.

Was able to get two in yesterday #3 and #4 it took me a bit longer by myself and with the block in the car still, so I raised a help flag for the family to help this weekend to get the rest in. Not sure how much this help will cost me or my wife in grandkids babysitting fees.  :D

Just need the time to get the heads over to the shop to be check and recondition.

The engine was done by a local machine shop around 2009-2010 and it sat on a portable roller for a few more years after it was done while I was getting the interior and body done. Im not sure what the old timer may had for reference at that time at his shop since he was a one man shop (with some temp helpers).   ???

What got me into this path was as I had mention above was the fouled spark plugs and smoking with two different heads (390 first and 365 now) on the engine. When I discover the rings were (IMO) clocked incorrectly and the gap was way above the specs. So only thing I can speculate at this stage the problem was caused by the shop, not sure if it was the owner itself or the helper whom assemble the block.  :(
Title: Re: Back to my smoking issue >:(
Post by: JAG56Cad on September 06, 2018, 06:32:47 PM
Well finally got a chance to get back to putting the old girl back.

Got the heads back and torque down per specs, got the valve covers back as well to get the oil pump going. Yes, had to connect the oil filter lines before priming the oil pump.  ;)

Turn the crank by hand slowly while continue driving the oil pump to proper lubricate everything. Notice the oil getting to the hydraulic lifter so move to the next test.   8)

Compression test done to all cylinders now Im seeing at least 20% increase on all with a range of 175 to 185 on all, now this was done with no intake manifold and all cylinders were wet from the initial installation.  :)

So happy days are here again, I hope! 

Next task is to get the rest of the gears back in and do the burn in test, fingers cross hope for smoke be gone.  :D
Title: Re: Back to my smoking issue >:(
Post by: Lexi on September 06, 2018, 06:54:16 PM
Fingers crossed for you as well Jose. Wish I lived closer as I would drop by to lend you a helping hand. Clay/Lexi
Title: Re: Back to my smoking issue >:(
Post by: South_paw on September 06, 2018, 07:01:49 PM
Enough testing.... fire that thing up  ;D
 
Title: Re: Back to my smoking issue >:(
Post by: JAG56Cad on September 06, 2018, 07:30:13 PM
Fingers crossed for you as well Jose. Wish I lived closer as I would drop by to lend you a helping hand. Clay/Lexi

Clay,

Thanks my friend Ill take a rain check..!

Although not sure you will take my offer with our current strange weather we are having one day is 99 temp mid-humidity and the next is thunder storms with 99 temp and 99 humidity.    ;D
Title: Re: Back to my smoking issue >:(
Post by: JAG56Cad on September 06, 2018, 07:31:06 PM
Enough testing.... fire that thing up  ;D

Lou,

If all goes well Im hoping to fire her up over the weekend, need to wake up early tomorrow to drop our daughter at the airport for her biz trip. Maybe I can get the rest done after I get back.   ;)
Title: Re: Back to my smoking issue >:(
Post by: Lexi on September 07, 2018, 08:50:00 AM
Fingers crossed for you as well Jose. Wish I lived closer as I would drop by to lend you a helping hand. Clay/Lexi

Clay,

Thanks my friend Ill take a rain check..!

Although not sure you will take my offer with our current strange weather we are having one day is 99 temp mid-humidity and the next is thunder storms with 99 temp and 99 humidity.    ;D

The weather wouldn't scare me off Jose! Besides it would be great helping you out with your '56 . Strange as it may seem our weather has actually been very similar up here this summer. Very hot, with lots of humidity, then rainstorms. Working on Lexi the other day it was 95 temp and very humid with scattered thunderstorms. Clay/Lexi
Title: Re: Back to my smoking issue >:(
Post by: JAG56Cad on September 30, 2018, 04:34:47 PM
Well after a few lost weekends with weather delays and changing wrenches from SAE to metric due to my wife Z3 car having an airbag warning  >:( , I finally had some spare time to pickup with my project.

I starter her again today and after a quick warmup it started to smoke again, oh not again  >:( >:(.  I realized my carb idle screws were all the way in, after getting them about 1-1/2 turns out all when well. Finally no more smoke happy days are here again..!

Still need to do more carb adjustment and getting the timing in, hopping for next weekend.   :)

I did hear what it sound like a lifter tapping on the left side  ??? would need to see how that goes next time, for the time Im happy my project can continue and hoping to have it done soon.