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Perhaps I missed it but did u use studs to guide the lower intake down perfectly to the heads? I use four bolts with heads cut off to guide my lowering. Also did u use a light coat of RTV sealer around water passages?
 

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Discussion Starter · #22 ·
Perhaps I missed it but did u use studs to guide the lower intake down perfectly to the heads? I use four bolts with heads cut off to guide my lowering. Also did u use a light coat of RTV sealer around water passages?
Based on prior recommendations by @Bestia from a previous post I did use studs to guide the intake down into the block and used the black RTV around the coolant passage. I also laid down a nice bead on the china rail vs using the gasket. That’s why I’m leaning towards the head gaskets as the issue still persists. Hope it’s nothing else after doing all this work…more work than expected for sure.
 

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I can’t wait to hear what you find. Don’t feel bad, we’ve all learned like this at times. Real world education isnt cheap!
 

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Discussion Starter · #26 ·
I started to take it apart until we lost power. Tonnes of coolant in the valley which could have happened when I lifted the lower intake off or it’s accumulated through the leak. With the outage going to spend some time trying to analyze it lol. What are other signs of lower intake gasket failure? Could it the rear coolant passage ports? Thanks
 

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Trying to look at the pictures what is under the gaskets between the gasket and the heads on both sides. Is that Orange silicone and goes on the top of the gaskets all the way across? You didn't silicone the whole gasket down to the head did you? Only supposed to put a little silicone around the water jackets. Some guys put weather strip adhesive on the backside of gaskets to hold them in place but very thin coats. But that looks like excessive amounts of silicone in pics under the gaskets. Your defeating the purpose of the gaskets doing that.
 

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You can try a leak down test before pulling the heads. If you hear air seeping out the block or see bubbles in the radiator, its a head gasket.
 

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Discussion Starter · #30 ·
Trying to look at the pictures what is under the gaskets between the gasket and the heads on both sides. Is that Orange silicone and goes on the top of the gaskets all the way across? You didn't silicone the whole gasket down to the head did you? Only supposed to put a little silicone around the water jackets. Some guys put weather strip adhesive on the backside of gaskets to hold them in place but very thin coats. But that looks like excessive amounts of silicone in pics under the gaskets. Your defeating the purpose of the gaskets doing that.
Nope I just put it around the water jackets, it’s surface rust that’s causing that orange look. I’ll look into how to do a leak down test and try it out. Thanks
 

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Discussion Starter · #31 ·
You can try a leak down test before pulling the heads. If you hear air seeping out the block or see bubbles in the radiator, its a head gasket.
Looked into it, this would require me to put everyone back together and purchase the leak down kit. I’m not sure if I should just keep going down to the heads or wait on the kit.
 

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Discussion Starter · #32 ·
Haven’t done much, keep going back and fourth on what to do next. Trying to wrap my mind around this if the block test detected a leak does that confirm it’s the head gasket or could the lower intake still be the culprit?
 

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Not an easy situation. I would personally put the lower back on and get everything buttoned and then start running some tests. You replaced the timing cover gasket also right? Did you use a little rtv around those coolant ports?

Run your tests and if everything looks good, then you know it was the lower. If it fails and you find out it is the head gaskets, taking the lower back off is only a 3 hour job max and $25 worth of gaskets.
 

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So it appears you put silicone between the water jackets on the heads between the gaskets. But didn't put silicone between the gaskets and the intake. Should be between both. And what torque setting did you torque the lower intake to?
 

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Discussion Starter · #35 ·
Not an easy situation. I would personally put the lower back on and get everything buttoned and then start running some tests. You replaced the timing cover gasket also right? Did you use a little rtv around those coolant ports?

Run your tests and if everything looks good, then you know it was the lower. If it fails and you find out it is the head gaskets, taking the lower back off is only a 3 hour job max and $25 worth of gaskets.
Yup timing cover gasket was replaced put the blue rtv around the coolant ports. Sucks I just did the lower intake gasket a few weeks ago thinking it would resolve this issue.

Wondering if Partsource provides the kit as a rental. Will call them tomorrow to figure it out.
 

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Discussion Starter · #36 ·
So it appears you put silicone between the water jackets on the heads between the gaskets. But didn't put silicone between the gaskets and the intake. Should be between both. And what torque setting did you torque the lower intake to?
I put RTV on both sides of the gasket around each coolant ports. I also put some directly on the head and lower intake on the corresponding ports. Is that wrong? Torque based on two steps with the first step at 15lbs and the second at 25lbs.
 

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Oh okay. It doesn't look like any silicone was between the gaskets to intake around the water jackets. Well it takes multiple time's going over and over the lower intake bolts torquing them down. I start by hand then grab a torque wrench. They keep loosening up and you have to keep retorquing as the gaskets compress. Just going around once at 15 ft lbs then a second time and 25 ft lbs isn't enough. And 25 ft lbs is the max torque rating. Should stop at about 21 ft lbs. Were you torquing the bolts starting in the center working your way out?
 

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Discussion Starter · #38 ·
Oh okay. It doesn't look like any silicone was between the gaskets to intake around the water jackets. Well it takes multiple time's going over and over the lower intake bolts torquing them down. I start by hand then grab a torque wrench. They keep loosening up and you have to keep retorquing as the gaskets compress. Just going around once at 15 ft lbs then a second time and 25 ft lbs isn't enough. And 25 ft lbs is the max torque rating. Should stop at about 21 ft lbs. Were you torquing the bolts starting in the center working your way out?
It pulled off clean and stuck to the intake itself.Ah 25lb is max hopefully I didn’t stretch anything. Attached a pic of the sequence I followed.
 

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It pulled off clean and stuck to the intake itself.Ah 25lb is max hopefully I didn’t stretch anything. Attached a pic of the sequence I followed.
Your torque sequence image is correct. Instead of going into the sequence at 15ft lbs, start off by putting all the bolts down until their heads touch the lower. After go through the sequence, 1/4 turn each, no torque wrench. Going straight to 15 ft lbs right off the bat could cause the lower to not sit flat. Once you did the 1/4 turn of each, go through the sequence again at 8ft lbs, then 15 ft lbs and finish off at 21 ft lbs (I went to 23 on mine). After that, wait an hour and final torque sequence again. After 24 hours, final torque sequence again. Once you’ve ran through a couple of heat cycles, remove the upper and final torque sequence again. I know the above looks to be overkill but it’s quite important.
 
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Discussion Starter · #40 ·
Thank you everyone for the feedback. Virtual beer for everyone! I’m trying to wrap my head around this, the block test indicating a leak could still have been caused from the lower intake gasket failing and the coolant leaking into the valley?
 
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