Rate my valves! Pics!!!

[mingmong]

Here are my exhaust valves on a 1977 Carrera 3.0 that had a re-build 25k miles ago. It was running but when they say in the manual 'a small puff of smoke at start up'...well mine was more 'cloud'. Looking though the inlet side they appear to have a whitish covering over them. Does this indicate 'running lean' mixture? How bad are they? Marks out of ten please. Cheers M

[Rondinone]

4. Have your mixture checked! That's too much carbon buildup in my opinion.

[mingmong]

Are you saying that they're actually OK, just need a clean? I was thinking (correct me if I'm wrong..newbe 'n all that) that the horrible black stuff at the bases of the valves was oil from worn guides. M

[camgrinder]

Looks more like 125k miles than 25k.
Did a reputable shop rebuild the engine?

[350HP930]

They LOOK OK, but that motor looks pretty grungy for having only 25K miles on a rebuild.

Unless someone drives WOT all the time carbon buildup is inevetible in a motor.

[mingmong]

Don't worry about the grungy look. All that oil around the piston cooler fins has dribbled down from the 'oil breather intake' thingy on top of the engine. Found that out when I took the intakes and ducting off. Easy to fix! Back to the valves...the general consensus so far is that they are probably OK and I shouldn't have to get new guides put in. Just need a clean up and adjust the mixture correctly? Would this stop the large 'cloud' of bluey oily smoke it used to emit on start up? I mean it used to run OK, plenty of power but quite thirsty. If that's the case then what's the best method of cleaning up these while they're in situ? So I can avoid purchasing the crows foot, cam socket and dial gauge which I'd probably only get to use once in my lifetime! Your views always appreciated M

[axl911]

This is what mine looked like.

How bad do these exhaust valves look

Worn exhaust valve guides.

---anthony

[mingmong]

Cheers Axl911.Yours look as good as mine! I guess it's time for new exhaust guides! Bugger!! More £££!! M

[hcoles]

IMHO - I am now rebuilding a 89 3.2 with low miles....mine were much worse than yours...I would say your motor is not in that bad of shape. I don't see the large black chunks I had. I had some valve guides that were very shot and I also had a ticking noise that went along with those. If you motor is hot and runs quiet and is not burning more than say 1qt every 800 miles then I would say your fine....unless of course you want to rebuild the top end for the fun of it. again this is IMHO.
-henry

[hcoles]

I just reread that you had a rebuild 25k ago....they seem a bit rough for that....it could well be normal but I hope mine are cleaner than what you picture after 25k....this could be in the range of what these engines do after only 25k miles....be interesting to see if you get more feedback. My vote would be a 5 out of 10 for 25k miles. IMVHO.
-h

[mingmong]

Now I'm getting confused! Should I get new valves or should I not? Don't really want to take the heads off as I've never done it before but then again why not give it a go while the engines out and partially in bits? Help me! What's the best cause of action?...I'm stuck in 'while I'm there land!' Cheers M

[axl911]

What's your oil consumpsion? How often and how much does it smoke?

I think the guideline is below 500 miles a quart is about time for the rebuild. If above, then you can wait.

I did mine at the 600 miles/quart. The other reason is the smoke is getting embarassing and choking me at stoplights.

---anthony

[afterburn 549]

If you are at the pt. where your heads are on the bench......and ask me about the valves,I'll say it again when in doubt throw them out! thats the best ans. -...if you think about the beating those things take and as much damage they can do..........need I say more?? (they are cheap insurance)
In my own engines porsche to lawn tractors...I hardley ever take a second look at a valve.....esp. a ex. V.

[mingmong]

Ahh..I only ever did about 500miles in the car before it died and I took the entire thing apart. So I'm not sure how much oil it was drinking. It used to smoke at start up when it hadn't been driven for weeks. Big 'cloud' of blue smoke then run clean. Smoked out the garage! Used to smoke when I stopped for petrol too but that was a different type of smoke and I found out that was due to the crumbled engine bay soundproofing melting on the hot engine! I think what I'll do is clean up what I can reach for now. Get it all back in and running and then do a compression test. If it's results are bad then I'll take it out again in the near future. Now that I've learnt how to do that it won't take so long or is it possible to do an accurate compression test with the engine out, manually cranking it? M

[afterburn 549]

how much can you wiggle the valves in the guide??? (side to side)?

[mingmong]

Haven't tried that ...I shall get wriggling once I'm finished work. Though I did read a thread saying that wriggling valves doesn't tell you much as the main wears on the piston side of things...and I don't have ET fingers! M

[Bill Verburg]

Clouds of smoke can also come from an overfill which gets sucked into the intake tract, I topped mine off before a DE once and sucked so much oil that it looked more like a forest fire. Took years to clean it all out.

That said if the stock Thermohedul guides are still there they are surly toast, the additional cost of new guides from where you are is reasonable.

[mingmong]

Would an over filled oil tank explain why there's alot of oil in my airbox. When I took the air filter off there was a film of oil at the bottom of it? Or is that normal? ...so much to learn...so little brain! Not sure if I'm still running on the original valves. I'll go through the paper history carefully tomorrow and try to find out. Cheers M

[snowman]

You likely have way to much carbon for 25k miles, looks more like 100k plus 25k. Your valve guides are likely to be shot, thats the usual reason for smoking at start up and excessive carbon buildup. Unfortunately you must remove the heads if you really want to know whats good or bad. If you can live with the way it runs, go with it, otherwise its teardown time. I would suspect whoever "rebuilt" the engine never replaced the valve guides. With a "rebuild" like this there may also be a whole bunch of worn out stuff as well. Some people think putting in a new set of rings and bearings is a rebuild, it isn't.

[mingmong]

I suspect you're right 'Snowman'. I've got pics of the valves and heads all nice and clean on a bench when they did the 'rebuild'. But I'm beginning to suspect that's all they ever did to them! M