R.I.P. lil 305...

[FordeatinZ71]

well, today was D-Day for my 305...sort of...at lunch i fired her up to move around to my toolbox so i could tighten my alternator belt because in the rain yesterday it was slipping. when i fired it up i heard this scraping sound which reminded me of another 305 i had that seconds after hearing that sound spun it's rod bearings . even though my oil pressure was fine i shut it down immediately. i checked my oil and the dipstick was hard to pull out...because it was RUSTY! see, i had just started driving my truck again after about a month or two of sitting, so the oil hadn't been checked in a few months. i know, shame on me...but thats how it happened. oddly enough though, the coolant is green and uncontaminated and the truck isn't overheating at all...also the oil pressure (or water pressure, lol) is perfect on it...holds around 45-50 at cruise and 30 at idle...)

so i had my wife bring me oil and i put in enough to fill it...fired it up and the noise was still there. after work she met me to follow me home "just in case". she wanted to do it, i told her i didn't need her to, i had confidence in my ol girl. on the way home i ran her hard (figured the motor was toast anyhow) and she ran like a champ (heck, maintained 80+ the whole way back with pedal to spare). got home and the noise was gone! but i know that the motor is worn out, so i'm gonna prep my 350 and throw it in post haste, along with a rebuilt tranny...

UPDATE! turns out the "rubbing" sound is the harmonic balancer which has slipped and is now rubbing against the timing cover.

[AyerForce]

I'd still move along with the 350, why not right?

[44gmcnewf]

drain all the oil out of it and drive it till it stops then put in the 350

[NovaMan]

LOL, you can't kill a 305!

[Ivan D.]

slipped harmonic balance calls for a new one, as it likely slipped rotationally as well, so instead of balancing it may be now shaking the heck outta that crank

[Ivan D.]

Originally Posted by NovaMan

LOL, you can't kill a 305!

Oh yes he can, just pull the oil pump drive shaft and see what hapens - that ain't no 302 that runs on zero oil pressure for thousands of miles (they do that, and no one really knows how or why, lol), kill the KY inside from flowing around and that 305 is toast! Now regular work and abuse, yes, I've seen some that according to logic shouldn't even be turning over, yet they pull a truck AND a 2-axle landscaping trailer behind it on daily basis!

[bob308]

i don't know what is wrong with a 305 last night gas was 3.65 a gal. so the only way a 350 is better is if you don't drive the truck or you are stock brokers with a large income.

[NovaMan]

Originally Posted by Ivan D.

Oh yes he can, just pull the oil pump drive shaft and see what hapens - that ain't no 302 that runs on zero oil pressure for thousands of miles (they do that, and no one really knows how or why, lol), kill the KY inside from flowing around and that 305 is toast! Now regular work and abuse, yes, I've seen some that according to logic shouldn't even be turning over, yet they pull a truck AND a 2-axle landscaping trailer behind it on daily basis!

Huh, I've never heard of a 302 lasting for any length of time without oil pressure. As a matter of fact, my Ford friends have to run alot of oil pressure in their 347 strokers to keep them alive.
The bolded part is more what I was talking about. I have a friend who was actually trying to kill his 305 with nitrous, and he gave up before the motor did.

[bored&stroked]

Maybe an old carb'd 302 with 7:1 compression can run on 5psi oil pressure but NO oil pressure? Not happening.

I say put the 350 in there quickly anyways. It is dang hard to kill 305's but its even harder to say no to more power.

[Ivan D.]

Originally Posted by bored&stroked

Maybe an old carb'd 302 with 7:1 compression can run on 5psi oil pressure but NO oil pressure? Not happening.

Snapped oil pump shaft, apparently certain older 302s have an issue with that, don't remember which ones tho - all I know is at least one goofball had a failure like that on a road trip to Florida, yet he was more busy thinking of all the tequila and girls waiting for him down in Panama City then about the funky noises coming from his engine - he drove his Mustang all the way down there, then back up to one of the east-coast states, and the darn thing never quit on him! A discussion was brought up on that topic, and it turned out it has happened before to other people, the funniest I remember was some soldier loaning his F150 to his girl who kept driving it for a month or so while he was off on a mission, he came home to a crazy sounding engine with gauge pegged at zero Like I said, no one really knew why these things never grenaded themselves, all logic says they should have, besides who really cares anyways - low pressure means big trouble, that's all there is to it.

[Ivan D.]

Originally Posted by bob308

i don't know what is wrong with a 305 last night gas was 3.65 a gal. so the only way a 350 is better is if you don't drive the truck or you are stock brokers with a large income.

Not even close - on a looong road trip I've seen 20mpg from my carbed 350, and before the carb died my big block in a jacked up 4x4 truck used to get better fuel economy than many of y'all with the small blocks. There's such thing as not enough power, meaning with a smaller engine in a heavy vehicle you'll likely have to work the engine harder to get the thing to move like it should, which translate in burning lotsa gas - if the larger engine was built right so it makes most power where you want it, it will not have to work anywhere near as hard as the smaller used to, so even tho the displacement is larger the overall fuel consumption can actually be lower. And considering our friend here is going to do his homework on the 350 build, I'd not be surprised if gets similar fuel economy numbers as he did with the stock 305.

[Ol'Rover]

send the old 305 to me

my 305 has almost 400,000Km on it and still runs like new. Sumthing tells me after i drop it in the C10 it may not last a whole helluva lot longer.

[FordeatinZ71]

lol, well, i really wanna build my 383...so i think i'm gonna throw in a new harmonic balancer ($50) and a good, clean dipstick and see how much longer she runs. i don't think the HB slipped rotationally because the engine still runs smooth as silk. it HAS vibrated twice but it's been for a very short period of time. the truck isn't being driven now anyhow, it's waiting for it's new balancer. thanks for the replies guys...

oh, and i have to retort on the Ford thing. my first ever Ford was a 1978 F100 with the "unkillable" 302 in it. yep, the 140 horse haus. ONE TIME it overheated (the water pump impellar separated from the shaft, a very weird failure) on the way from an interstate trip and not only did it not make it to the house, that one time overheating DESTROYED that motor...so much for "impossible to kill"...guess i'm just good like that.

now, gotta give some props to a 305. my first TPI F-body, i had a 1987 Firebird Formula with a TPI 305 and a 5-speed. car was fast as HELL for being stock and ran awesome. i overheated it a few times because the front air dam was missing (it fell off on a long trip, so i overheated it a few times going down the freeway) and it never missed a beat (i'd just pull over when it got too hot, just like with that dern Ford). anyhow, fast forward a year down the road, i decided to pull the motor and prep the car for it's new engine (was going bigger) and as part of the removal process i drained the oil. STRAIGHT antifreeze came out for 30 seconds before oil did. i swear on my deceased grandfather's grave, that car didn't smoke at all, still hauled butt and only had a slightly rough idle.

now i've seen some 302's that were awesome, and i love the Ford 302, but the 305 isn't to be discounted at all...it is a strong-weak engine...lol

[GreaseDog]

mine has been warm a few times, 280-290 in the last derby truck, and still all oil in the crankcase. added a SUM-1102 cam when it was still in the original C10, damn tough little motor. i guess that's why its still in the garage.

[retired wrench]

I wonder why they call them harmonic balancers and not static balancers??? RW

[NovaMan]

Well, although some do have balance weights, they're really harmonic dampeners.