Just got finished removing & cleaning the lower intake manifold on a 1999 Ranger 2.5L XLT automatic after quite the struggle. Coolant was suddenly below level on the reservoir & was slowly draining after topping off over time so I rented a radiator pressure tester kit to find the leak but couldn't find it visually so I searched online & found out the engine could just be burning it through a leak on the lower intake manifold gasket. Verified by feeling moisture under the lower intake manifold, but the area around the valve cover was also moist so I also chalked it up to replacing the valve cover gasket as well ☹️ . The lower intake manifold gasket had cracks, chipped off pieces & was very brittle when I finally got to it.
Now the Haynes's manual says to "clean & oil the manifold mounting bolts". Does that mean 1) just wipe it off with a clean rag & squirt WD40 on them or 2) soak a rag with brake cleaner, wipe off the red stuff from the threads, replace them with Permatex #2 red slow drying non hardening sealant, squirt WD40 on the threads before the sealant & bolt the manifold within 5 mins (which sounds almost impossible to me given the cramp space to work with)?
Will the old thread sealant still even hold given how long it's been there? Or is that red stuff Loctite?
Haynes even says to apply a light coat of sealant on the gasket to hold it in place, but Fel-pro says no (I didn't see any RTV on the old one). I plan on carefully hanging the gasket on the bolts if that's even possible.
I'm concerned that there might be a slow leak & have to redo it again & I'm not looking forward to do that as it has been a PITA just to remove the bolts in tight quarters.
As far as tightening & torque sequences, I'm planning on following the number sequence, finger tightening the first step, & running it off with a cordless ratchet or just snugging it on cramped areas instead. I've had bad luck lately with breaking off bolts even with a torque wrench & I'm not looking forward to doing that on the engine head. There might not be enough space to even fit a torque wrench on the lower intake. Haynes says to finish it with 19-28 ft-lbs, but 28 might be a bit much. There's a Mazda B-series torque spec that only goes to 22.
Thanks.
P.S. I was too focused on the leak on the intake side that I didn't look at the possibility on the exhaust side. How do I check for a leak WITHOUT coolant?
Tips to make the job easier:
1. Soak the nuts & bolts with rust penetrant over night. The 2 upper intake bolts near the firewall are a PITA to remove & you'll need all the advantage you can get.
2. To give you more space to get to the hidden upper intake manifold bolt from hell & the EGR nut, remove the ECM harness with a 10mm along with the plastic hanger & ground eyelet.
3. Use a 10" adjustable wrench & loosen the 27mm nut to remove the EGR from the EGR tube. Save yourself the trouble of replacing the EGR gasket (doesn't come with the Felpro intake manifold & valve cover gasket set). I ruined the EGR intake manifold threads accidentally because it was out of alignment when I bolted it back on from prying it away to get to 1 intake manifold bolt hidden under the EGR. 😡 Bought a pair of U nuts & 1/4" bolts with end threads because of space limits on passenger side. Used blue Loctite for added security.
4. If you have a 1/2" socket, use it instead of a 13mm. You might get away with the 13 for other bolts, but you'll round off the 2 upper intake bolts nearest the firewall. Bought an extractor set specifically for the job, but that didn't help. I needed to hammer in the socket with the 1/2" & use the cheater bar from heaven (4 ft pipe) to deal with the bolt from hell 🙂 Believe me, my 1/2" axle nut busting impact driver couldn't budge the bolt for some reason.
5. Tape the 4 corner bolts securely to the lower intake manifold & hang the gasket on them to help with alignment. The bolts won't fall off + you won't need to glue the gasket to the intake.
Without coolant, you can still pump up the cooling system with air to see if it holds pressure.
Will the old thread sealant still even hold
I haven't worked on Fords much, but when I look at the gasket shape, the mountain bolts are completely surrounded by gasket material. And correct me if I'm wrong, but the bolt holes are blind (don't go through). Which means the bolts are only providing clamping force. They don't do any sealing at all.
Fel-pro says no
Follow the instructions that came with the gasket
