Engine rebuild plan

[Darkfader]

Hi guys and gals, my 409/2x4bbl, which I must assume is not original to my car, 1964 Impala SS, is leaky and a bit smokey as well. It seems to run great, but I notice quite a bit of moisture from the tails during warm up along with some light grey/white smoking after warm and letting off the throttle. There is no oil in the antifreeze or vice versa. It’s been driven less than 200 miles in 2 years of ownership and I’d say less than that by the previous owner.
I’ve been told my valve seals are probably failing resulting in oil entering the combustion chambers, causing the smokey exhaust on decel. Maybe the piston rings are worn as well. Don’t know. This along with the oil leaks that I can’t seem to pinpoint with the engine in the car are making me want to yank the engine this coming winter, and give it a good refresh.
That said, I’d prefer not to overbore the cylinders if the walls are in good shape. I’m not interested in finding more hp either. This car is strictly for relaxed cruising in nice weather only. The goal here is a reliable cruiser with no fluid leaks.
I see Show-cars has a pretty inclusive kit for engine rebuilds. How do you guys feel about these kits. I’m also highly interested in the edlebrock heads made for the 409 as well. Any tips or insights would be highly welcomed and greatly appreciated. I’ve rebuilt a few engines over the years but I’m new to the 409. If my research is correct, I believe I have a 425hp 409 from a ‘62 pass car. Here are some pics of casting and pad numbers. The car looks pretty on the outside but definitely needs work underneath as far as leaks.

 

[Phil Reed]

You are correct on all your information!!!!!!!!
Try to find a shop or a good old mechanic to check out everything you listed. You are the right track!!

 

[Don Jacks]

First off there was no 425 house 409 made in 62.This was a 63-64 package.On the overhaul,if the bores are straight [little to no taper],free from scratches,and round[little to no out of round],there's no need to rebore the cylinders.While there's nothing wrong with the Eddie heads,if a good freashen up on the existing heads would be just as effective and cheaper.I'd wait until the engine has been dismantled and measured before ordering parts.Since this is going to be a "daily Driver' reliable,fun driver I suggest going with a mild hyd.roller cam.If the pistons in there don't pass muster replace them with forged pistons,not the cheaper cast junk.Show Cars[dr409] is a great place to deal with and they'll customise their kits to suit your needs.

 

[Darkfader]

Thanks Phil, I do have a trusted machine shop for hot-tanking/inspecting the block once it’s out and bare. I’d like to perform the other work myself. I’d love to remain stock as far as bore, cam, etc. It appears if I went with the edelbrock heads I’d need their rockers and pushrods at a minimum. Still researching that. I suppose I need to weigh cost of existing head rework versus new heads and supporting parts.

 

[Darkfader]

First off there was no 425 house 409 made in 62.This was a 63-64 package.On the overhaul,if the bores are straight [little to no taper],free from scratches,and round[little to no out of round],there's no need to rebore the cylinders.While there's nothing wrong with the Eddie heads,if a good freashen up on the existing heads would be just as effective and cheaper.I'd wait until the engine has been dismantled and measured before ordering parts.Since this is going to be a "daily Driver' reliable,fun driver I suggest going with a mild hyd.roller cam.If the pistons in there don't pass muster replace them with forged pistons,not the cheaper cast junk.Show Cars[dr409] is a great place to deal with and they'll customise their kits to suit your needs.

Ah, my mistake. With my suffix code of “QB” I referenced the chart under ‘64 and saw the 425hp designation. With my casting number and QB, does that mean it’s the ‘62 409hp then?

 

[Iowa 409 Guy]

If you go with new heads Bob Walla Racing is a good choice. He's a member here and has a 409 car. Good guy to deal with....

 

[Don Jacks]

QB stands for the 2x4bbl. high performance 409 engines.In your case,yes,the 409-409 engines.Which exhaust manifolds do you have on the car now? Daves right.If I were going to aftermarket alloy heads for this engine,I'd get with Bob Walla,hands down.

 

[Darkfader]

Currently there are tubular headers installed on the car and Flowmaster mufflers. The welds on most of the piping are subpar and I will definitely want to install a cleaner exhaust system that fits better.

 

[427John]

As far as pulling the engine for a total overhaul especially when you are happy with the way it runs and the amount of power it has,just doesn't make sense to me.Most if not all of the issues you list can be addressed with the engine in the car and without removing the heads.Unless a leakdown test shows that you have some serious cylinder pressure issues,or the oil leaks you speak of involves the rear main seal I would be inclined to address them in the car.Now if you are mainly concerned with performing a show quality engine bay detailing and want to address any issues while the engine is out then your on the right track.Something people need to keep in mind about any factory high performance engines that remain at their as built specifications,except for the oil leaks you mention the symptoms you describe weren't considered abnormal for high performance,high compression engines with forged pistons and assembled with slightly looser than standard clearances,I don't know about GM but I do know both Mopar and Ford both included paperwork with the new cars with HP engines that explained this to the new owner.I would be surprised if Chevy and Pontiac didn't do this also.While I'm not trying to say there is nothing wrong with your engine,i would say that it does warrant more diagnosis before deciding it requires rebuilding.If you watch old movies and footage from racing events you see that a lot of the engines do exhibit some smoke to varying degrees.

 

[Tom Kochtanek]

You do have a passenger block circa 1962, the "068" casting on the rear flange and the "QB" stamping on the front pad confirms that. Those are quite desirable . You probably have the "690" castings for cylinder heads. Looks like an "881" dual quad intake. Nice combination. When you get the chance, let us know which numbered carbs are under that chrome air cleaner. The 2x4 chrome air cleaner was used on the 1963 and 1964 models that had the 425 HP rating. In 1962 that rating for the dual quad setup was 409 horses.

If you decide to yank it out, I'd freshen up what I already have, but then I prefer "iron" versus "aluminum" except when it comes to intakes .

Or you could send it to me and I'll put it one of my 1962 passenger cars .

So, while you don't have a "numbers matching" or even "period correct" block and heads, you do have a combination a lot of guys will be envious of, congrats!

Keep us posted as you go through things, collectively we give great advise, you get to make the decisions (and foot the bills!) .

Cheers! TomK

 

[Tom Kochtanek]

Forgot to mention, in 1964 the high perf engines had cast iron exhaust systems of the "swept back" variety. The casting ended in 925/926. They are kinda hard to find in good condition and somewhat costly. There are lots of header options, Wilson being a good choice for performance and proper fittage .

Best, TomK

 

[Iowa 409 Guy]

Several guys here have the Wilson's and seem satisfied with their performance. FWIW order a year in advance.

 

[Darkfader]

Great information so far, I thank all of you. I will definitely keep up with the thread as I move forward.
If I don't need to pull the engine, then I won't. It's not as clean as I'd like it be though and I feel like if it was out and on a stand, after hot-tanking, it could get fresh orange paint and all the bracketry and accessories could be thoroughly cleaned as well. Not to mention, I feel that replacing gaskets would be much easier with the engine on a stand. However, I don't want this to turn into a multi-year project so I'd want to use the upcoming winter months to complete everything. I have a 2-post lift, and engine stands and hoists and a press and all kinds of fun stuff in the garage so labor would only cost the amount of beer I keep out in the garage fridge.

When I get back to the house, I'll snap some more pics of everything to share.

 

[427John]

When anybody reads my posts they need keep in mind I am definitely a form follows function kind of guy and that cosmetics will always be secondary to me,I'm not bashing someone that is important to,its just not me and my posts will be tainted accordingly.

 

[IMBVSUR?]

Great information so far, I thank all of you. I will definitely keep up with the thread as I move forward.
If I don't need to pull the engine, then I won't. It's not as clean as I'd like it be though and I feel like if it was out and on a stand, after hot-tanking, it could get fresh orange paint and all the bracketry and accessories could be thoroughly cleaned as well. Not to mention, I feel that replacing gaskets would be much easier with the engine on a stand. However, I don't want this to turn into a multi-year project so I'd want to use the upcoming winter months to complete everything. I have a 2-post lift, and engine stands and hoists and a press and all kinds of fun stuff in the garage so labor would only cost the amount of beer I keep out in the garage fridge.

When I get back to the house, I'll snap some more pics of everything to share.

When your done detailing that engine, I have another one for you. I'll even supply the tools and beer

 

[409gang]

Making water during warm up is a sign of a motor with good compression which is a result of compressing air unless it is coolant, a wore out motor will not make moisture. As far as smoking during deceleration that is a sign of worn valve guides and or bad valve stem seals. Before you tear down that motor I would do a compression test on it, you might need to only freshen up the heads and chase the oil leaks.

 

[427John]

Yes one of the byproducts of combustion of hydrocarbons and oxygen is water vapor which will condense as water in a cold exhaust system.It is still there after warmup its just not as visible as steam.

 

[Darkfader]

Making water during warm up is a sign of a motor with good compression which is a result of compressing air unless it is coolant, a wore out motor will not make moisture. As far as smoking during deceleration that is a sign of worn valve guides and or bad valve stem seals. Before you tear down that motor I would do a compression test on it, you might need to only freshen up the heads and chase the oil leaks.

Yes one of the byproducts of combustion of hydrocarbons and oxygen is water vapor which will condense as water in a cold exhaust system.It is still there after warmup its just not as visible as steam.

I was hopeful that a new set of valve seals would solve the smoking I get. I'm not sure why it would only happen during deceleration. and it's not every time I let off the gas either. I'll definitely do a compression test and report back with my findings. I was in a grueling program last year and unable to devote a lot of time to it, but now my schedule has let up some and can give it some attention. if I can avoid a costly R&R, I'm all for that.
Judging by the condition of the rubber components in the suspension, I can only imagine what the rubber that I can't see looks like. I definitely want to order all suspension bushings and body mounts this week to get that squared away.

Is there a "wiggle test" to measure valve guide wear? I know my LS7 had a shade tree method of judging guide wear. I had also read a thread or two about replacing valve seals without removing the heads using air pressure in the cylinder. I'll look around for those again. I do have the 1961 big book and 62, 63, 64 supplement shop manuals.

 

[409gang]

When your throttle is closed and the pistons are on their intake stroke it will tend to suck oil thru the valve guides as the pistons are pulling a vacuum on the entire intake system including the valve guides. If your guides or seals are bad you will see smoke when you step on the gas after declaration when the engine clears out the oil it sucked into the cylinders.

 

[409gang]

Most of those old cylinder heads have worn out valve guides and just putting new seals on won't take care of the problem. If you take your heads into a shop have them check the guides and if needed put in new guides.