When to overhaul your 1975 302

[1975DBronco]

Hi, i have a 1975 Ford Bronco with a 302. I believe it was overhauled in the early 90s but after the previous owner and myself the mileage is pretty high. In search for an answer what is the average mileage when you should overhaul the 302?

 

[1969]

I don’t think it’s so much about an exact mileage in my opinion. But more so how the engine is such as does it have excessive oil consumption, noticeable loss of power, rough idling, hard starting, knocking noises, low compression, excessive blowby? Race engines have relatively low mileage on them and still need to be gone through. I’ve seen engines with 200k on the clock that look and drive like “new”.

 

[Speedrdr]

My 2 cents is that you look at oil consumption and noticeable reduction in power to tell you when it’s time to freshen up the motor rather then mileage.

Randy

*** @1969, you beat me to it it. lol ****

 

[Broncobowsher]

Either bad noises (rod knock) with glitter in the oil. Or just excessive oil consumption.

 

[.94 OR]

You could check your timing chain wear if you just want to look at something.
Take the cap off the distributor, manually turn the engine over until the timing marks are visible.
Turn the engine in reverse direction watching both the timing marks and the rotor. When the rotor starts to turn it has taken up the slack in the chain.
Rule of thumb is anything over 7° of rotation and it is time for a new chain and gears.
If you are to that point, you may want to look at other parts too.
How is the oil pressure?

 

[Broncobowsher]

7° would still be a decent chain for high mileage. About 1/8 of a turn of the crank is when I decide to start planning on going in.

 

[DirtDonk]

To paraphrase Indiana Jones “it ain’t the mileage. It’s the years…“
Then again, it ain’t the years either. It’s the use, abuse, quality of the previous rebuild, and all sorts of other factors, too numerous to mention.

 

[1975DBronco]

Tha

I don’t think it’s so much about an exact mileage in my opinion. But more so how the engine is such as does it have excessive oil consumption, noticeable loss of power, rough idling, hard starting, knocking noises, low compression, excessive blowby? Race engines have relatively low mileage on them and still need to be gone through. I’ve seen engines with 200k on the clock that look and drive like “new”.

thank for the Information, I will keep that in mind

 

[Madgyver]

disconnect speedometer cable, you'll be surprised how much farther it goes..

 

[jamesroney]

Hi, i have a 1975 Ford Bronco with a 302. I believe it was overhauled in the early 90s but after the previous owner and myself the mileage is pretty high. In search for an answer what is the average mileage when you should overhaul the 302?

The correct answer is "never."

Unless you are driving a concourse restored trailer queen, that is stone stock with emissions requirements...the answer to the 302 rebuild question is:

Go get a 5.0 Roller long block from an 87-96 Ford 5.0 HO. No one has ever regretted doing this.