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Valve stem seals? Guides? Or????

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lesingepsycho

Jedi Warrior
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Hello everyone.

So far my engine build hasn't been going as smoothly as I had hoped for. I'm still blowing smoke pretty badly. Anyways, here's my latest discovery: oil in the intake runners. Diagnosis?

This head was just rebuilt by the guys at "British Auto Works" to the tune of $373.36 which supposedly included "Labor rebuild head, install hardened seats, surface head, hot tank and clean, install double valve springs, assemble head" <-Quoted from receipt.

What do I do?

JACK
 

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Did they install new guides?

Do the intake valves have seals on them?
 
See, that was my point in quoting the receipt. I would have assumed if you're going to do all that work, you would install new guides, heck, they're cheap enough. But now I guess I don't know for sure. I am pretty sure that they put new seals on the intake valves but I guess I'm not 100% positive there either.

You know, I took it to "British Auto Works" because you would assume that they would know these things like the back of their hand but I'm starting to feel like they did a pretty hack job. I was expecting to get back a head that was like new and ready to run. That doesn't look to be the case. Unfortunately I don't think I have any recourse so I'm feeling like I'm basically out almost $400 and I have an engine that doesn't run and it is yet to be determined if this has done any damage to my brand new engine that I have a GIGANTIC chunk of change in.

JACK
 
Was this head on the car before the head work?
If it was I would think that the guides were good enough to not be the cause of the smoke your seeing.
Maybe they didn't install new seals?
You said you installed a new cam in the other post could the lift be high enough to crush the seal and pump oil down the guide? It can happen :smile:
 
Though it would be nice to expect a rebuild to include new guides, my suspicion is that since they were not mentioned on the invoice... the guides were probably not replaced. That said, I would expect (without exception) that the rebuilder would fit new seals on the intake guides. New seals won't fix worn guides but for at least a short period of time they will slow the amount of oil that gets burned. Can you at least see intake seals between those double springs?
 
Oh man do I love my machine shop.
$100 for a head job, $150 if he has to install new guides and deck it.
And he does test it for both cracks and leaks after he is finished.
And I guess $25 bucks a hole to bore it is cheap too.
For $300 the block gets tanked, the cylinders get bored, the rods get checked and fixed if not round, and he installs the pistons on the rods and gaps the rings.
In fact, the last engine I sent him came back with all that for $270.
Not including the head which was done a few months earlier for $150 with new guides and a shave.
 
Well, I guess I'll have to pull the valve cover and see if I can see the seals.

Attached is my cam grind sheet from Elgin. Is .303" considered a big increase in lift? Enough to smash the valve seals? If so, how do I rectify that problem? Increase the valve clearance? Also, I noticed that the Elgin sheet has clearance numbers listed. I set the rocker clearances to .014" like the manual states. Could this be a problem? Bigger clearance would mean less travel, would mean less smashing of valve seal? But what about valve clatter?

JACK
 

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I don't know if .303" is excessive lift or not. However, you did say at the start that this head has double valve springs. I have heard many stories of people collapsing the springs (coil-on-coil) because they are using a high-lift cam and long ratio rocker arms. My point is, I think it is more likely that your double valve springs will collapse to coil-on-coil and when that happens it's unlikely that anything can/will come into contact with the seals.
 
Can't grind new(or any) valve seats with worn out guides. (well, you're not supossed to.) so I think maybe he did change them.

Do you have oil in the intake?

Any chance it might be comming from further up?
 
How far up the intake manifold does that oil extend?
Swab it with a q-tip.

You have crankcase vents connected to intake or air cleaners, make sure the oil isn't coming from there.

Also, did you ever answer my query on age of fuel and whether or not you might have accidentally added something exotic, like, oh, chain saw mix or diesel?

The normal flow on intake pulses is not generally going to allow puddling of oil that far out.
Oil from an intake guide/seal will run straight down onto the back of the valve, and into the combustion chamber.
However, if it is massive, yes, you could puddle up on the back of a valve, and spill into the port, but look at your picture.
That would mean every wet port would have to miraculously have the intake firmly seated shut.

If the guides are shot, you can see the movement just by yanking the valve cover, finding an intake fully closed, watch the stem tip, and move the spring/retainer back and forth.

You see movement on the stem, you've got problems.

I've seen a whole lot of that in diagnosis, but generally not after a rebuild.

You just need to do due diligence, so you know what needs to be done when dealing with the shop.

Dave
 
I never installed valve seals on my new heads. I remeber I tried it once and they were knocked off in the first hour of running. That said, the engines never smoked.
 
TOC said:
How far up the intake manifold does that oil extend?
Swab it with a q-tip.

You have crankcase vents connected to intake or air cleaners, make sure the oil isn't coming from there.

The normal flow on intake pulses is not generally going to allow puddling of oil that far out.
Oil from an intake guide/seal will run straight down onto the back of the valve, and into the combustion chamber.
However, if it is massive, yes, you could puddle up on the back of a valve, and spill into the port, but look at your picture.
That would mean every wet port would have to miraculously have the intake firmly seated shut.


You just need to do due diligence, so you know what needs to be done when dealing with the shop.

Dave
Click to expand...


+1

what he said.

Last thing you wanna do in get up in their face and it's something else.
 
Thanks guys,
I was a little hot under the collar yesterday and as you all have said, I needed to do due diligence.

I checked and I have the new valves and valve guides and valve seats listed on another invoice so we can assume they were all installed new. Today I pulled the valve cover and made a visual inspection and I can see valve stem seals on the 4 intake valves.

While I was in there, I went ahead and set the valve clearances to the specs on the cam sheet. I fired her up and the smoking seemed to go down but is still there. I may just need to get out and burn it off at this point and get some mileage on the new rings. Up to this point it has been too smoky to even be considered road worthy.

Oh, and to answer Dave, I had just put a brand new tank of gas in the car when the other engine blew. The tripometer shows 14 miles on the car and then I pulled the engine, no additives of any sort. This gas was about 2 weeks old when the engine was first fired.

Thanks again everybody,
JACK
 
Did the tank have cosmoline in it?

Did you check futher up the intake to see if it was oily there?

Got a pic of your intake? Isn't that the same spot the injectors are firing?
 
I did disconnect the crankcase vent to be sure.

I have no idea what cosmoline is, so no.

I had already reassembled the intake with a new gasket so I didn't see how far up the intake runner the oil was.

Right now I'm running the Weber DGV. I haven't got the EFI hooked up yet.

JACK
 
I haven't seen any history of what happened with the old engine. You say it blew up?

What about the smoke? does it come when the engine is first started, or does it come some minutes later?

The question here is: How much oil is there in the exhaust system. A blown engine can put a lot of oil out the exhaust, and if it's still there it will burn off after some time, but not right away.

These engines don't usually smoke due to valve seals. The factory seals were shi. Just an o-ring around the valve somewhere above the guide. It did nothing! The engines never smoked anyway.

The inlets look ok, except for that black spot. Is that burned or otherwise carbonized oil? If it is, where did it come from and why is it burned? Nothing should be burning in the inlet manifold.
 
Cosmoline is a grease like substance put on new steel parts to keep them from corroding. It might help it smoke, but it won't put oil in the intake.
 
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