Supra Forums banner
21 - 40 of 41 Posts

·
Registered
Joined
·
141 Posts
Discussion Starter · #23 ·
No change, drove it to work - did a bunch of pulls. My usual routine. Did some errands after, never any smoke.


Sent from my iPhone using Tapatalk
 

·
Registered
Joined
·
1,397 Posts
I'm not buying the fuel enrichment thing if that's your conclusion. Blue smoke is oil. Fuel is grey/black. There are a few possibilities remaining if it's blue smoke. On a fresh engine, I'd take the time to pull the spark plugs and check them for differences. A "sometimes" symptom like yours is often specific cylinder, and due to a the position the engine happens to stop. Like a one in 40 startup condition, or similar.
 

·
Registered
Joined
·
1,397 Posts
Yeah, winter is on, eh? Here as well. You guys getting any snow up there? Just a few dustings in town, and the mountains are not covered as much as usual by now. I've got a couple snowshoe treks planned, so hoping it's a good snow winter, or I'm moving up near you!
 

·
Registered
Joined
·
141 Posts
Discussion Starter · #29 ·
Yeah, winter is on, eh? Here as well. You guys getting any snow up there? Just a few dustings in town, and the mountains are not covered as much as usual by now. I've got a couple snowshoe treks planned, so hoping it's a good snow winter, or I'm moving up near you!
Yeah there is snow on the ground but 14 this weekend, bye bye snow lol


Sent from my iPhone using Tapatalk
 

·
Registered
Joined
·
141 Posts
Discussion Starter · #30 ·
Blue smoke on start up is your valve stem seals.
Nah head is new, only happened 2 times that day. Never before never since. Not looking into it any further at this moment

Builder said enrichment map


Sent from my iPhone using Tapatalk
 

·
Registered
Joined
·
17 Posts
Nah head is new, only happened 2 times that day. Never before never since. Not looking into it any further at this moment

Builder said enrichment map


Sent from my iPhone using Tapatalk
Head is new? I had my head resurfaced and cleaned and then reinstalled. My car blew blue smoke prior to this work being done. Started my car after and the blue smoke on start up was worse. I was dumb founded the machine shop/ mechanic didn't replace the valve stem seals. I thought this would have been standard practice. As a result I replaced them myself with the head still on and it was not fun. Any ways blue smoke was 100% gone on start up after replacing them.
 

·
Registered
Joined
·
1,397 Posts
My car's head was pulled for a head gasket and reinstalled for $1800 for the OP. They did not adjust the valves, nor replace the valve seals. On a then - 30 year old engine! I suspect this happens a lot as valve adjustment and seal replacement take skills a level above the neanderthal level needed to replace a head gasket.
 

·
Registered
Joined
·
17 Posts
My car's head was pulled for a head gasket and reinstalled for $1800 for the OP. They did not adjust the valves, nor replace the valve seals. On a then - 30 year old engine! I suspect this happens a lot as valve adjustment and seal replacement take skills a level above the neanderthal level needed to replace a head gasket.
Don't they boil the head to clean it.....I know the head gets hot when installed but wouldn't this ruin the rubber seals? Mine were rock hard.
 

·
Premium Member
89 Turbo Targa
Joined
·
84 Posts
This does amaze me in the fact if having head work done that valve seals are not replaced.
Years ago that was a given, not something you had to make sure was done or had to ask to be done.

The shop here that took my head off, for the MHG & ARP’s, did the valve stem seals just because.
They also knew not to lap the valves.
Lapping valves on a 50k mile engine would just creat blow-by on the rings.
 

·
Registered
Joined
·
1,397 Posts
Supratrbo - a full head disassembly would permit that type of cleaning but for a head gasket a shop would not do that in general. My head shop does - they are phenomenal. But thats my gripe is a shop working on a 30 year old head should replace the seals and charge for it. Nobody wins if the customer pays $2000 and a month later its blowing smoke.
Skipshot - not sure I understand the link between lapping valves causing ring issues. I think someones giving you sketchy info there.
 

·
Registered
Joined
·
17 Posts
Supratrbo - a full head disassembly would permit that type of cleaning but for a head gasket a shop would not do that in general. My head shop does - they are phenomenal. But thats my gripe is a shop working on a 30 year old head should replace the seals and charge for it. Nobody wins if the customer pays $2000 and a month later its blowing smoke.
Skipshot - not sure I understand the link between lapping valves causing ring issues. I think someones giving you sketchy info there.
The head was sent out to be resurfaced and it was checked for cracks and repainted. There is no one on this earth that would say no to replacing the valve stem seals at that stage. Going forward if I ever have head work done again I'll verify the shop 1st.
 

·
Premium Member
89 Turbo Targa
Joined
·
84 Posts
From the old days...
Seal the top & bottom will leak.
Seal the bottom & the top will leak.

If you pull the head off a 100,000m car, do a valve job to seal the valves (Grind/Lap) you'll end up pressurizing the block. Doesn't cause the rings to be bad, it will cause by-pass. I've seen a head job done then end up throwing oil out the dipstick.
Seen people do the opposite, bottom end re-built with new rings + hone the cylinders, you'll hear air passing your valves ending up with puffing in the exhaust.
Not to be confused with a burnt exhaust valve puffing...
 

·
90T
Joined
·
1,054 Posts
I had a 75 Civic that I did a valve job on and after that it burned oil badly until I did the rings. Of course this just means that the engine was shot and needed a complete rebuild. I did not have that problem when I did the valves on my 7M even though it had many more miles. I guess engine durability has improved since 1975, who knew? 😂
 

·
Premium Member
89 Turbo Targa
Joined
·
84 Posts
I had a 75 Civic that I did a valve job on and after that it burned oil badly until I did the rings. Of course this just means that the engine was shot and needed a complete rebuild. I did not have that problem when I did the valves on my 7M even though it had many more miles. I guess engine durability has improved since 1975, who knew? 😂
Yep, on high mileage engines that aren't in good shape that's exactly what happened to me.

Threw that out there just in case.
If there's blue smoke on cold start-ups I would just replace the valve guide seals... wouldn't go with a valve job unless a compression check shows good rings.

Thinking out loud, on newer engines with tighter tolerances, this may not happen like it did on my 65 & 66 Mustangs?
Anyone done this on our cars to see if that's still not a good idea?
 
21 - 40 of 41 Posts
Top