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Smoking exhaust after warm-up

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bighly

bighly

Jedi Knight
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My 60bt7 exhaust smokes after full warm-up.

Engine was rebuilt by unknown builder 700 miles ago.

Over 200 lbs compression on all but one cly 195

Running 10w40 - (changing to 20w50 today)

When oil filler cap is removed I do get spray from the rocker oilers (I assume 3-4 inch squirts since it makes it just out the filler cap hole on valve cover).

I assume the oil is getting into the cylinders from the top.

What do I check? I have read in related threads that this all points at good compression rings but something worng on the head.

It runs pretty well but the smoke is worrysome not to mention embarrising and ecologically irresponsible.

I just vant to drive. Perhaps I am facing a "do-over" on the head and valve-train.
 
The rockerarm assembly is spraying oil because it is worn and this is very common. The extra oil is getting by the valve seals and the result is the white smoke. The oil should just seep out slowly and this will reduce the oil getting by the seals.

There is a place called Rocker Arm Specialist in Anderson California who's name says it all. You send in your old rocker arm assembly (simple to remove)and they will do complete disassembly, straighten rocker shaft, center grind undersize, hard chrome plate and regrind to current spec. The rockers are refaced, new screws and nuts, and new bushings installed and honed to size. All this for about $98.00 last time I checked. They also make Roller Rockers for the 4 and 6 cyl. motors. More valve opening, smoother running at higher rpm.

The contact info is at:
https://www.shastacounty.com/rockerarm/

cheers.gif
John
 
John,

I'll bite. What are rolling rockers? The Stones will be here in the SF Bay Area this month if that counts.

Tracy
 
Hi Tracy,

I guess the Stones count but you still get the white smoke
wink.gif


Follow the link for pictures of the Roller Rockers from RAS. Note the Roller tip of the rocker arm ... this keeps the force pushing straight down on the valve instead of swiping the rocker arm tip across the top. Advantages include less wear on the valve guides, true 1.5 ratio geometry, slight HP increase, smoother engine at higher rev's, make better use of high performance cam.

https://www.loftusdesign.net/rollerrockers.htm
Cheers, John

[ 11-03-2002: Message edited by: John Loftus ]</p>
 
John

Your link didn't work for me. I got the HTML page, but no pictures. I would love to have the details of these rebuilders for furute reference. $98.00 is a lot sweeter sounding than the ~$400.00 price tag I've seen from other suppliers. Don't need it this week, but.....

Thanks again
Thom
 
John

Thanks very much.

BTW the reason that I don't see pictures is because the image tags are referring to your "C" drive: "file:///C:/Clients/Healey%20stuff/Roller1.jpg"

Looks like one of those "Front Page" snafus that I love to hate.

Thom
 
Thom,

Hopefully the link is working now but here is one of the Roller Rocker pictures. BTW, these cost approx. $350 for the 6 cyl. versions.
roller2.jpg


-John
 
I just spoke to Blain at the rocker place.

120 to rebuild as standard. 450$ for a rolling rocker assy.

I'll stay standard but this is great info for future enhancements.

BTW 20w50 made a big difference compared to the 10w30 I was running. I will pull the rockers off tonight and send them out. 1 week turn around.

Thanks for all the help.

Tracy
 
Hello Alec and Tracy,

If the rocker arm assembly is squirting large quantities of oil it stands to reason that there will be more oil pouring over the valve seals and if they are leaking there will be more blueish white smoke. I know that my puffs of smoke were greatly reduced by having the rocker assembly rebuilt and there was an added benefit of higher oil pressure. It also makes sense to have the valve guides and seals redone when/if the head gets pulled. The stock seals are little O rings and many recommend to instead go with full umbrella type seals.

Cheers,
John
 
Hello bighly,

As you have found out the right oil grade helps. Two points; doing the rockers will not alter any oil leakage through the valve stems which may be the cause of the smoke. Top end leakage usually shows at idle and when you accelerate after lifting off the throttle. If you keep your foot hard down and the smoke clears, it is valve leakage.
A new engine takes some time to really bed in but shouldn't be smokey. A compression test will confirm good seal, (valves and pistons) but will not show if the oil rings are working. (BTW it is blue smoke if its burning oil) White smoke is brake fluid sucked in from a defective brake servo.
good luck,
Alec
hammer.gif


PS, don't get too paranoid about the ecological impact of your smoke, it's a big world.

[ 11-04-2002: Message edited by: piman ]</p>
 
Piman,

Your advice is good, but your P.S. is way off base. It is a big world with tens of thousands of old cars. It is our responsibility to make sure they are as clean as can be. If we don't the nay sayers will have their way annd remove them from the streets and rightly so.

Scott
 
Sometimes, removing the hose that runs from the rocker cover to the back carburetter will help verify that you have a bad rocker shaft. The rockers at the back of the engine tend to squirt the oil right down the hose and into the carb. Result: Instant blue smoke without the need for bad valve seals. If you remove the hose and it's oily inside you have your first clue. If you drive around with it off and the smoke disappears or is greately reduced, you have your second clue. If the engine is now covered with oil directly below the dangling hose, you've hit a home run.

Good Luck
Keep us posted
 
Thanks to all who helped. My daughter and I had a great driving day today. The rebuild on the rockers sorted the problem out.

The leaves are changing up at Hecker Pass Wineries and Autumn feels great!!
 
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