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hope its just a head gasket?

needswork9450

Well-Known Member
so i checked my oil the other day and have a problem. i have antifreeze mixed in with my oil but my car is not overheating nor is there any knocking coming from the motor. in fact the motor never really gets warm it stays cold. wtf is goin on? btw its not leaking anything under the car either.
 

Tommy

New Member
definitely sounds like a head gasket. Possible prior over-heat???

worse case scenario it can be cracked heads, which are relatively cheap to replace stock heads. If it's either a gasket or warped/cracked heads, this a great opportunity to upgrade to GT40 heads. They can be found easily and under $300 ready to bolt on.

Get a new Camshaft in there while you have the majority of the engine apart :hello:

GT40 heads, E-Cam and GT40 intake = noticeable torque increase :rock:
 

02gt

Well-Known Member
yeah i would go with some TFS heads, with a nice cam, give it some balls...LOL
 

atlblue98gt

Greer, SC
by the way. He may be swapping out the 302 for a 351. It has the same mounting points doesnt it? Since a 351 is a 302 bored out?
 

510z

Well-Known Member
there is more to a 351 swap than just bolting it in, you will most likely run into hood clearance problems, you can find a set of convertible mounts wich will give you up to 3/4" more clearance, but odds are you will still need an aftermarket hood to clear.

you will also need an oil pan and pick up, there are a couple different pans out there for this swap.

the 351w is also a 28oz inbalance so you wont be able to use your 5.0 flywheel or balancer, FRPP offers a billet steel, SFI-approved 157-tooth flywheel (M-6375-A302) that will work, and assuming you wish to use the factory serpentine belt system, you can use the FRPP steel damper (PN M-6316-C351), along with the M-8510-B351 or C351 spacer, which creates the proper alignment with the serpentine system.

your intake will not work on the 351 either because of the taller deck height of the 351 so you will need to source another intake.

Your stock 302 power-steering and air-conditioning (if so equipped) brackets will not work on the 351W, so you need to get the brackets from frpp.

you will also need to get new headers because the 351 is taller so the 302 headers will not work.

then you will need to think about fuel system, you will also need a distributor from an efi 351 as your 302 unit will not work.
 

510z

Well-Known Member
first thing i would do is do a leakdown test imo, water can come from an intake gasket also.
 

needswork9450

Well-Known Member
how do i do the leakdown test? i'm still driving the mustang cuz i don't have the time or the extra car to work on it right now. i'm parking it in about 2 or 3 weeks when i get another car to drive and probably gonna take it completely apart and re do everything from the rotating assembly up. gonna take some time but i was thinking about the 351w to put in it so i could build it to drag. its a complete motor and tranny set all it needs is a battery. all other parts are included. its out of a mid to late 80's f-series truck. not real sure what year tho
 

atlblue98gt

Greer, SC
truck intakes are normally taller. id say start looking for a 2 to 3 inch cowl hood if you wanna do that swap. i have a stock 98 gt hood that you can use to cut a hood scoop. thatll be cheaper. but dont know how good you are at body and paint work.
 

510z

Well-Known Member
how do i do the leakdown test? i'm still driving the mustang cuz i don't have the time or the extra car to work on it right now. i'm parking it in about 2 or 3 weeks when i get another car to drive and probably gonna take it completely apart and re do everything from the rotating assembly up. gonna take some time but i was thinking about the 351w to put in it so i could build it to drag. its a complete motor and tranny set all it needs is a battery. all other parts are included. its out of a mid to late 80's f-series truck. not real sure what year tho

A leak down tester uses air from a compressor and measures the rate at which it leaks through the engine. This is done with the engine not running and the beauty of this is that toy can find the source of the leakage by listening for the escaped air. Internal leakge is found by air bubbles in the cooling system. Tools need are a leakdown tester, and an air compressor. The can be had for about $60.00. Compressor should be at least 2hp and deliver 90psi.

Remove spark plugs. Set engine to TDC #1. Calibrate test gauge per the instructions. Lock engine so it can not turn. Connect hose to spark plug hole, Connect pressurized gauge to hose connection. Read leakage. If looking for coolant leaks and nothing obvious shows up, bypass gauge and connect shop air direct to cylinder. Open radiator cap before this. If coolant sprays out, you have a head problem. Do same test on rest of cylinders. Remember to set TDC of each piston for compression stroke. This test is also great for air cooled head leaks and valve problems. Note that all engines will have some leakage past the rings. I always do full pressure test when I suspect a problem. Make sure engine is secured with full pressure test. it will spin violently. With gauge connected, you can rock crankshaft to see if leakage changes. If so, this is a sign that the ring lands are wearing, new engines will also do this until the rings are seated.
 

510z

Well-Known Member
how do i do the leakdown test? i'm still driving the mustang cuz i don't have the time or the extra car to work on it right now. i'm parking it in about 2 or 3 weeks when i get another car to drive and probably gonna take it completely apart and re do everything from the rotating assembly up. gonna take some time but i was thinking about the 351w to put in it so i could build it to drag. its a complete motor and tranny set all it needs is a battery. all other parts are included. its out of a mid to late 80's f-series truck. not real sure what year tho

do you have emission testing where you are at? if not that will definitely make some things simpler, you are not going to want to run the truck intake.

if there is no emissions testing or it will be drag only, going carb will simplify that part, the heads on the 351 are junk and being mid to late 80's it will not be a roller block
 
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