73-87 Chevy _ GMC Trucks => Engine/Drivetrain => LT/LS Swaps => Topic started by: lwilson on April 24, 2015, 10:10:37 AM

Title: 1984 C10 in Colombia, South America, Milky Oil!!
Post by: lwilson on April 24, 2015, 10:10:37 AM
Hello, greetings from Colombia, South America. I will try to be short, but explain dilemma, because English is not my first language.

1984 Chevrolet C10 Custom, RWD, I-6 Engine, converted to run gasoline/Natural Gas.
SM-465 manual transmission with 3rd gear issue
Owned for 1 year

Milky oil, engine shutting off, overheating, low power. Removed cylinder head, found coolant in front-most cylinder. Changed head gasket, oil pan gasket, side cover gaskets, valve cover gaskets, exhaust manifold gasket, torqued head bolts to 125 ft-lbs, except for 1 bolt at front passenger side which was different. Torqued exhaust manifold as per factory Chevrolet manual. Added black RTV silicone to head bolt threads to prevent leaks from bolt holes. No silicone on head cylinder gasket.

Started truck, same issue with milky oil. Removed head, took to machine workshop hydrostatic test PASSED. Head no leaks, cylinder head is FLAT. Even though integrated head/exhaust can have cracks, all was OK.

Only thing I noticed was the larger valves on the cylinder head bottom were wet while the smaller were dry.

What do you recommend can be the issue? Machinist and parts are very expensive, so will consider LS swap from USA if fix is too $$$.

Picture of Maybe Scratched Red Gasket Material at Frontmost Cylinder Lower Left Hand Side of Picture:

Title: Re: 1984 C10 in Colombia, South America, Milky Oil!!
Post by: Irish_Alley on April 24, 2015, 11:25:48 PM
welcome from maryland. i cant help you with the engine due to im not at all familiar with the inline 6. but keep faith and be patient, cause i know we have a couple who are familiar with them. oh and about your English, you type it better than some of us and its my first language lol
Title: Update - Resleeve or New LS Engine
Post by: lwilson on June 03, 2015, 11:01:24 AM
Well, I understand there is not much experience in USA with Inline-6 engines, mostly V8 over there. Today I paid machinist to come out with caliper and measure cylinders. I had changed new water pump as last hope of cause of mixing oil + water. No luck.

Machinist said number 1 piston (closest to radiator) that was leaking. Also said top 1/2 of cylinders 2-6 is out of round, but bottom half of cylinder is round and to specifications. Cost to install new sleeve in Cylinder 1 is about $125 and then wanted to machine other cylinders and install new bigger piston heads. Machinist said at same time would have to change exhaust valve seats because they were worn with Natural Gas fuel use. And also would have to polish crankshaft - total cost about $1,500-$2,000 USD to machine Cylinders 2-6, new piston heads, crankshaft, re-sleeve Cylinder 1.

In summary, I will do cheapest option and only re-sleeve Cylinder 1 and see if engine runs okay. If not, I will make arrangements to bring LS or LQ4 engine from USA, maybe with 4L60e or 4L80e automatic transmission. I do not want to put more money into an old I-6 engine when I can get better MPG with new fuel-injected V8 and cheaper parts, more power, new transmission, etc for about same price as fixing old engine.

Please, my question to you is what is complete list of parts for new LS engine swap. I have I-6, so I need V-8 engine mounts to mount sliding LS engine adapter? And I maybe need transmission adapter to adapt old driveshaft to new auto transmission. And maybe short exhaust manifolds? Will 4l60e/4L80e fit in old transmission tunnel?

My biggest worry is how to get new LS engine and transmission computer tuned and working with old gauges or is cheaper/easier to buy new digital gauges??
Title: Re: 1984 C10 in Colombia, South America, Milky Oil!!
Post by: Irish_Alley on June 03, 2015, 11:23:40 AM
moved it to the LS board so it will get the attention of others
Title: Re: 1984 C10 in Colombia, South America, Milky Oil!!
Post by: Captkaos on August 14, 2015, 11:22:55 AM
You won't be able to use all of the gauges stock on the 84, the speedo won't work.  It won't be cheaper or easier with a set of Dakota Gauges, but they will work.  If you are not intimidated by wiring, it will be simple.