Need Help with Diagnosis Please!!!

[BigWheel]

Symptoms: slightly rough idol, strong rich smell that almost burns the nose, slight smell of antifreeze. I know the air intake tub going into the throttle body has a tooth missing where it connects so also hearing a slight sucking noise.

Head has been replaced, all seals and gaskets replaced. No oil leak anymore. Doesn't stall or hesitate just slightly rough. Any ideas??

[FB71]

Symptoms: slightly rough idol, strong rich smell that almost burns the nose, slight smell of antifreeze. I know the air intake tub going into the throttle body has a tooth missing where it connects so also hearing a slight sucking noise.

Head has been replaced, all seals and gaskets replaced. No oil leak anymore. Doesn't stall or hesitate just slightly rough. Any ideas??

you just identified your problem; air leak in inlet tube. Causing a lean reading on the O2, which causes the ECM to enrich the fuel mix. Too rich a mix will cause a random misfire, as will a still-leaking head gasket (possible source of coolant smell).

[BigWheel]

you just identified your problem; air leak in inlet tube. Causing a lean reading on the O2, which causes the ECM to enrich the fuel mix. Too rich a mix will cause a random misfire, as will a still-leaking head gasket (possible source of coolant smell).

Dang I'm good and didn't even know it :p. One is easy to fix but the other isn't. I'll check the HG this week. If the HG is leaking I'm gonna be a little ticked. Long story but I'm a shade tree mechanic and I have spent more time fixing the problems my mechanic's helper caused when replacing the head. He tried three times to fix and oil leak that I fixed in one sitting. His problem was clamping the VCG down too tight rendering the gasket useless. I can only imagine if he didn't know how to tighten the VCG correctly he probably didn't know how to tighten the HG either.

[FB71]

Dang I'm good and didn't even know it :p. One is easy to fix but the other isn't. I'll check the HG this week. If the HG is leaking I'm gonna be a little ticked. Long story but I'm a shade tree mechanic and I have spent more time fixing the problems my mechanic's helper caused when replacing the head. He tried three times to fix and oil leak that I fixed in one sitting. His problem was clamping the VCG down too tight rendering the gasket useless. I can only imagine if he didn't know how to tighten the VCG correctly he probably didn't know how to tighten the HG either.

I'll guess he didn't actually torque the head, just tightented the bolts and guessed at the torque. That would slightly distort the head and cause the gasket to leak.

[mechanicaldj]

I'll guess he didn't actually torque the head, just tightented the bolts and guessed at the torque. That would slightly distort the head and cause the gasket to leak.

also a possibility of the throttle body gasket leaking coolant into the intake and a vacuum leak

[FB71]

also a possibility of the throttle body gasket leaking coolant into the intake and a vacuum leak

very good point, forgot about that as a source.

[BigWheel]

also a possibility of the throttle body gasket leaking coolant into the intake and a vacuum leak

Found two problems: [1] Air intake tube had a break in it and [2] the TB gasket is missing. Now wouldn't you think that when a mechanic took everything apart he would have thought to put a gasket back on? I'm starting to feel a lot better about my mechanic skills. I'm having to fix his repairs.

[FestYboy]

only way to learn is to do it yourself! i'd pull the valve cover anyway and borrrow an accurate torque wrench and check the head bolts @ 75 lb-ft. if they click right away, they're too tight, and if they don't you won't be overtightening them too much (5 lb-ft).

[BigWheel]

only way to learn is to do it yourself! i'd pull the valve cover anyway and borrrow an accurate torque wrench and check the head bolts @ 75 lb-ft. if they click right away, they're too tight, and if they don't you won't be overtightening them too much (5 lb-ft).

If the head bolts are over torgued will backing them off be enough to fix a leak or will this require a new gasket? I know that's a loaded question but the reason I ask is the VCG was over torgued and it was a pancake when I removed it.

[FestYboy]

you;ll need a new gasket (most likely), i would replace it if the head is too tight.

[FB71]

only way to learn is to do it yourself! i'd pull the valve cover anyway and borrrow an accurate torque wrench and check the head bolts @ 75 lb-ft. if they click right away, they're too tight, and if they don't you won't be overtightening them too much (5 lb-ft).

Spec is 60ft/lb for the head bolts.


TORQUE SPECIFICATIONS
Description_______Nm __ Lb-Ft __Lb-In
Cylinder Head Bolts 75-81 56-60 —

[BigWheel]

As I posted before I found the two vacuum leaks and will fix that tonight. After driving the car today I immediately opened the hood and noticed coolant on the driver's side hood just above the battery. In looking at the pattern it looks as though the coolant is spraying on the bottom side of the hood and then running down from the center of the hood across the engine. I cranked the car and kept it running looking for a pin hole. Can't find anything. No trace. Tried reving the engine and nothing. The cap is new and holding pressure so where ever the leak is it has to be very mall. Ideas?

[FestYboy]

hmmm i must have taken them down a bit too hard (thought i remembered 70 lb-ft for some reason).
Jim, you think i botched the HG by going the extra 10#s?

[BigWheel]

Overall I am extremely pleased with how far I've come with getting Hot Rod running. For the first time HR is running very smooth, with more horse power and only a slight smell of coolant. As a matter of fact I got Hot Rod on interstate today, up to 75 mph, and not a hitch, skip or hesitation. Now the last issue. I'm still losing coolant. I've checked the head, the TB and lower hose to find nothing. On one occassion I found coolant on the driver's side just over the battery on the bottom side of the hood. I can't find a pin hole or anything else. There's no oil in the coolant and no coolant in the oil. Only thing I can imagine is a pin hole somewhere. Is there any way to test the coolant system to find a leak?

[FB71]

hmmm i must have taken them down a bit too hard (thought i remembered 70 lb-ft for some reason).
Jim, you think i botched the HG by going the extra 10#s?

well, technically, you over-tightened them by 15-20ft/lbs, but no, I don't think you did any real damage.