Help fix engine rattle under load | Tbird 69 429ci

[OlDirty]

Hello,

I'm a 69 Tbird 429cui driver from Germany. Ford 385 engines (and Big Blocks in general) are rare over here, so it's hard to find qualified help.
My engine rattles pretty loud under load. Moreover it flares a lot of (probably bluish) smoke from the exhaust, when quickly pushing the pedal all the way down. And for example when the street is wet and I'm idling at a fixed position, I can see residues/thin film of gas on the street right under the exhaust tips.

I hope these information help to isolate the problem and fix it. If you need more information, please let me know.
It's a completely stock 429cui ThunderJet engine with the Autolite carb.

I need step-by-step advice on what to check or do first, because after being able to do almost anything at the body I'm just beginning to learn more about engine stuff (although most basics aren't completely new to me).

Thanks and best regards!

 

[CT8]

Do a wet and dry compression test. first do a check on the crankcase ventilation.

 

[Kawiguy454]

+1 compression check will tell you something about general engine health.

While you're at that check each spark plug for COLOR. They should all look similar TAN color (google it). If you have one or two off color note the cylinder it is. overall dark/Black may be oil burning from ring problems or valve guide/seal which would explain the smoke.

If it rattles under load only I would think immediately spark knock from low octane gas or too much ignition timing/advance.

If the spark plugs are very white/clean this would indicate lean fuel mix spark knock. Check the breaker points and ignition timing also is correct.

 

[DSparks]

Sounds like the typical 60's high compression engine with [censored] gas and agressive ignition timing....only real fix is good gas.....retarding the timing and richening the carb is a crutch and turns these old engines into dogs......A set of D3VE heads(later lower compression) and bumping the timing back up is a decent fix and it will be fairly happy and liveable.......only other thought is drive it like a PxxxY but thats no fun lol..

 

[yvon_la]

likely valve oil seal! and the carburator accelerator pump seal is likely shot .carburator is a cheap thing to fix but you might want to wait for the valve oil seal till you get the time. lastely make sure your gas as enough octane and isnt with ethanol!the carb oil seal get shot about every 2 or tree year the way they installed it back then ,but you should ask here how to install this properly , i am pretty sure our nascar maniac have trick to make the accelerator pump ring last longer ( often made of leather back then

 

[4wheeldog]

Is it using substantial amounts of oil? If it is, the smoke and the pre-ignition are related. Burnt oil creates deposits in the combustion chambers, which raise effective compression. The deposits also tend to have hot spots, which can ignite the mixture early.

As others said, do a dry and wet compression test. Don't be too surprised if you get a wide range of numbers. Any readings higher than standard indicate the condition I outlined. Lower readings indicate rings failing to make a good seal. There is a good chance you will need to replace the rings.

Or.....You could get a tank of the best gas available, and run it wide open on the Autobahn for an hour or two. That might actually work.

 

[fdcg27]

That car wouldn't survive fifteen minutes wide open on an unrestricted highway, much less an hour or two.
The cooling system was never intended to deal with that sort of use.
Still, I think you may be on to something.
The rattle could be preignition resulting from carbon buildup on the piston crowns and in the combustion chambers.
I'd try a water spray decarbonizing as a first resort.
If the problem is the octane rating of available fuels, a full time water injection system might cure it.

 

[4wheeldog]

Originally Posted By: fdcg27
That car wouldn't survive fifteen minutes wide open on an unrestricted highway, much less an hour or two.
The cooling system was never intended to deal with that sort of use.
Still, I think you may be on to something.
The rattle could be preignition resulting from carbon buildup on the piston crowns and in the combustion chambers.
I'd try a water spray decarbonizing as a first resort.
If the problem is the octane rating of available fuels, a full time water injection system might cure it.


You have little faith in old school 'Merican engineering. Not that I had much exposure to beasts with engines the size this Tbird, but back in that era, I ran a few V8s wide open for an hour or more across Nevada. It was even legal. Most were geared way to high to allow the engine into the danger zone.

The issue is not whether it could do it, if in top shape.....The question is.....What maintenance has not been done.

But.....Discretion being the better part of valor.....A 15 minute wide open dash on the Autobahn might be just enough.

 

[Lyman]

Old V8s run rich and get carboned up. They need to be blown out on a regular basis. Get it out and run it hard for a bit. It does sound like you might have some other issues but I'd start with a compression test and a tune up.

 

[Chris142]

Originally Posted By: DSparks
Sounds like the typical 60's high compression engine with [censored] gas and agressive ignition timing....only real fix is good gas.....retarding the timing and richening the carb is a crutch and turns these old engines into dogs......A set of D3VE heads(later lower compression) and bumping the timing back up is a decent fix and it will be fairly happy and liveable.......only other thought is drive it like a PxxxY but thats no fun lol..
I agree. That 429 may have 10-1 or higher compression.It requires premium fuel. 60's premium was 94 or higher octain. What octain is available there?

 

[dnastrau]

The '69 Ford 429 required a minimum of 98 Research octane here in the US. Today's US and Canada pump gas lists the Research and Motor octane numbers averaged, so 93-94 octane here today is the same as 98 in Europe which is still the Research method like we used in the 1960s.

98 Research octane premium should be readily available in Germany as far as I know.

Andrew S.

 

[Kruse]

I actually own a '69 Ford LTD with the 429 and 2 bbl. carb and C6 transmission. (Does your car also have the GM starter that has the solenoid on the starter motor as well as the separate solenoid switch? Mine does)
You are hearing detonation and you need to find the absolute highest octane gas that you can find. The blueish smoke that you see would be the piston rings not being able to handle oil control when there is the detonation.
My "step-by-step" advice would be to first run a tank of 100+ octane aviation gas in this car and then see if you have any rattles or blue smoke.
You won't.

 

[Merkava_4]

1. Change to stiffer distributor advance springs
2. Set ignition timing to zero BTDC

Either that or fill up with 110 octane fuel (or whatever it was back in 1969)

 

[OlDirty]

Wow, so many answers! This community is simply amazing.
I will start with a tank of high octane fuel. Like dnastrau said, our octane numbers are calculated differently. I always filled it with 95 octane fuel yet, which conforms to ~91 octane in the US. The highest I will get here is something like 100+ octane, which corresponds to a ~95 octane (or more) US fuel. At some stations it's even called racing fuel. Pretty expensive though, but if this is the problem...why not use it. I run it less than 2000miles per year anyway.
I will also run it wide open for a few minutes. Luckily we have those parts on the Autobahn without a speed limit.
What do you think of engine cleaning additives in my case?

 

[Chris142]

If you can get race gas run it.

 

[Merkava_4]

Putting heavy advance springs on and backing off the timing is like putting ankle weights on a human. You're losing a lot of performance but you don't have to worry about pre-detonation destroying your piston rings on pump gas. I've done it before with a high compression engine in a 1970 car; it works.

 

[artificialist]

If your car produces more smoke after idling for a long time, then a short puff of smoke happens when you accelerate, you migh have failing valve seals. Sometimes you can just replace the valve seals, sometimes you have to have the cylinder head rebuilt.

Back in the 1960s and earlier, exhaust valve seats were protected by the lead in gasoline. In some engines, the factory valve seats could handle unleaded gasoline, but other engines couldn't handle it. That can lead to problems with valves, and in this situation, cylinder heads have to be rebuilt.

 

[Rhymingmechanic]

If you take the advice to blow the carbon out on the Autobahn, please fill with high-octane first, and back off if it still pings.

Have you been able to check the timing, to make sure it's set properly according to the underhood decal or a service manual?

 

[OlDirty]

I didn´t have the chance to check anything yet. Just filled it with race fuel and it ran pretty good. I have to check it for some more miles though.
But before I can proceed I have to fix another problem. Yesterday my Purolator fuel filter broke into pieces after only 100mls and I had fuel all over my engine. I´m happy that it didn´t catch fire. Moreover it leaks fuel when starting the engine (which is always a pain in the [censored]). I assume it´s the float valve.
Of course I will keep you updated

 

[Kruse]

Originally Posted By: OlDirty
Yesterday my Purolator fuel filter broke into pieces after only 100mls and I had fuel all over my engine. I´m happy that it didn´t catch fire. Moreover it leaks fuel when starting the engine (which is always a pain in the [censored]). I assume it´s the float valve.


Sounds like you need a new fuel filter. I guess you need to look at something other than Purolator.
You probably need a new carb kit installed. Ford carbs of that era like to leak around the accelerator pump. Check to see if there is a small tin tag (with a few numbers) on top of the carb being held down by a single screw. It should be there...unless the last person to work on your carb left it off. It MIGHT help to have these numbers when you order a carb kit. Otherwise some brands of carb kits have enough extra parts to get you by.