914-SHO Serious Motor Issue?

[3d914]

I've started tearing down the motor so that I can get to the valve covers. In the process I removed the air-vent hose from the bottom of the throttle body (vent hose #1 in pic).

After doing so I thought I drained a little coolant from this hose. It was clean coolant - not brown or dirty at all.

How can this be? Could something be crossed in the throttle body allowing coolant into the intake portion?

 

[Shovert]

I can't answer your question but have a idea. I assume know if coolant or condensation. I assume not condensation since not running engine long? Of course I don't know how humid it has been? Could rent or borrow the tool that goes on the radiator cap to pressurize the cooling system thru the radiator cap. Maurice

 

[Phoenix]

Wait what? That bottom hose links directly to the inside of the TB , it feeds the fumes of the engine block into the intake to be burned...

Thats not right...

 

[rbruso]

I believe you plugged the lines to the TB that would have carried coolant, correct? If so, no coolant should be in your intake at all. If you did keep the coolant lines to the TB or the IAC spacer double check all line routing.

If enough coolant came out of that line for you to see, you should be able to put some paper towel on a pipe cleaner or a bit of wire and slide it into the port to verify if there is any coolant in the line.

You should also be able to pull the four bolts holding the vent onto the block and look inside for evidence of coolant. This is part of the crankcase ventilation system, which normally has some suspended oil. As such, any coolant that shows up should mix with the oil and make it look sludgy.

 

[3d914]

I'll pull the intake off tomorrow, check the vent as suggested and get back with you.

Thanks

 

[LOUDSHO92]

Was it maybe one of the throttle body de-icing/heater hoses?

 

[intimdatr]

Was it maybe one of the throttle body de-icing/heater hoses?

Thats my thought. May have got one of the lines mixed up?

 

[hawkeye18]

Well, coolant certainly wouldn't have made it through the PCV system [such as it is] clean.

Have you bypassed the TB coolant loop? If you haven't, I'd start looking there.

 

[3d914]

Well, coolant certainly wouldn't have made it through the PCV system [such as it is] clean.

Have you bypassed the TB coolant loop? If you haven't, I'd start looking there.

Jason, you're correct about the PCV system. When I pulled off the hose that goes from the TB to the front valve cover it was quite dirty - but just fuel-scented gunk, nothing more.

I also topped up the engine oil and it was very clean - so no contamination there.

I don't have any of the TB coolant lines hooked up. Nor do I have the coolant loop that ties into the IAC.

It's possible it could have been condensation as Maurice suggested since that section of tubing does sag and could trap moisture. But I thought I saw the green coolant tint to it. Will check some more this evening so I don't have to guess.

 

[3d914]

Well looks like maybe false alarm for the coolant in the line. Got out and checked it after work. Since I plugged the hose it had a little more fluid in it. Definitely water-based and not coolant color. Must have been due to condensation from hot engine to cold garage overnight and old-man's eye sight. The ****** on the underside of the TB had some slightly gunky looking fluid - similar to what I saw on the other TB/PCV port.

New issue though. I pulled the valve covers off and noticed one of the bolts was not torqued properly. Definitely appears stripped. Are these inserts or threaded directly into aluminum heads?

 

[black92]

These are threads in the head, no insert. You'll want to use a Heli-coil.

 

[3d914]

These are threads in the head, no insert. You'll want to use a Heli-coil.

Thanks, got any details on correct size? Doesn't look like there's a lot of room to grow.

 

[black92]

You buy the Heli-coil for the size bolt you have.
I dont know off the top of my head the Valve cover bolt size, but take it to a NAPA or similar store, they can size it for you, and get you the proper size heli-coil. The Heli-coil package "should" have a chart and tell you what size to drill it out. Guessing 1/8" larger or close to that.

 

[probe_racer]

i would use a time-sert or keensert if you are going to do that on the head and they stay in better.

they are a bit more expensive but the peace of mind is priceless.

 

[3d914]

i would use a time-sert or keensert if you are going to do that on the head and they stay in better.

they are a bit more expensive but the peace of mind is priceless.

That was the plan. Don't trust helicoils (BTDT)

 

[3d914]

OK, found a time-sert repair kit for the M6 x 1.0 x 10mm threads in the head. The hole's blind about 20mm deep, but the threads only occupy about half that depth so a 9.4mm time-sert should do the job.

I'll add some pics when I get it all done.

 

[black92]

I just came across a need for thread repair. I was unaware of time sert. I did some research and decided to give it a try.

 

[3d914]

I just came across a need for thread repair. I was unaware of time sert. I did some research and decided to give it a try.

Most of the heads I've worked with are aluminum and the helicoils just don't hold with the soft metal and heat cycling. Time-serts have always done the job in these cases. The only thing better would be to flood weld and re-drill & tap.

 

[3d914]

Didn't want to forget to post my results on this issue. The details of installing the time-sert are over on my project thread here.

But here's a picture of the final result. Very easy to do. Just takes a little patience.