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Cat 977L - overheated it, and now water in cylinder 1 (Cat 3306 engine)

JohnnyAirtime

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Joined
Feb 23, 2017
Messages
37
Location
Alpine, CA
Good day gents....
I recently aquired a 977L (along with a 931B - and love'em as they have 4-in-1 buckets). However, when I took posession of it off the trailer I had to drive it from dropoff location down into a canyon and back up to my house via a steep switch back. About a mile long dirt path. My 1200ft long driveway is concrete and steep up/down with turns. Not nice for a semi with lowbed.

I didn't check the coolant (or any fluids actually) before doing this... but the 977 had run fine when being worked on for cylinder seals and other "fixes" before I took posession. It was part of the deal.

When I was coming UP towards the back of my property, it started to get hot. I was in 2nd (yes, my mistake - new operator/owner issue) but couldn't stop (too steep). I idled it down, sat and let it cool down, then moved the last 20feet to a flat switchback turn. It was about 85 degrees out that day.

I came back that night, now only 55-60 degrees and put 4gal of water/coolant in the rad. Drove it up to it's resting spot (longer than the first leg and this time in 1st gear), and later added another 6gal to "fill" the rad. That last run up to the resting spot it never got hot or even too warm. However, when I went to start it the day or two later... it blew water out the exhaust. It was pressurizing the radiator too (cap off, water is blowing out the cap - not just water pump movement).

Now... the head is off, and no tell-tale visible signs of it just being a head gasket. But cyl 1 was full of water. Also, the precup on cyl 3 was loose. Finger tight loose.

I'm in San Diego.... anyone know of a place to get the head checked? Or, would it be better to just buy a reman head and go from there? I'm hoping the cylinders are okay and we don't have a cracked block. The pressure in the rad was quite a bit... seemingly more than just a crack could enduce. But... I'm not a mechanic, it just seems like common sense.

If I buy a reman head.... know of any places with such?! My mechanic knows, and is waiting for me to call local machine shops. But they aren't too many around anymore. Plus, it's Christmas Eve!

THOUGHTS from the 3306 experts?!
 

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bam1968

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Nov 1, 2014
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664
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IA
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Excavating Contractor
I'm going to go out on a limb and say that this was an issue before it got delivered to you. How long did it run from the time you unloaded it until you noticed it was hot? 20-30 mins? If so, I am pretty sure you would have noticed that much coolant/smoke coming out of the exhaust if it just happened when it was delivered. BTW there is nothing wrong with running it in 2nd gear. I'm not a fan of running them in 3rd gear but second if fine. I overhauled a 3306 in a D6H a couple months ago that I bought on an online auction. Stupid mistake. I unloaded it off the trailer it idled for about 15 mins while I paid the trucker then drove it about 100 yds to park it beside the shop it was boiling hot!!! Shut it off. About an hour later I started it and it blew a bunch of coolant out of the exhaust. Ended up being a cracked head. IIRC it had 2 precups leaking as well. BTW previous owner had put a reman PC motor in it. Thats just the tip of the iceberg on this machine!!! Anyway, take a look at the #1 cylinder on the head it's very possible you can see the crack/cracks if you clean it up and look closely. I hope you get lucky as coaldust said and it's only precup leaking.
 

bam1968

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IA
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What kind of Frankenstein is this? That had to take some effort.
I don't want to derail this thread but that is exactly what it is. When it came down to trying to figure out the engine serial #'s and arrangement #'s I PM'd Nige. He was a huge help because the guy's at Cat couldn't seem to figure it out. It is a smidge short on power but it's up nd running now.
 

bam1968

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From his previous thread it looks like the machine s/n is 11K4920.
 

Nige

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Jun 22, 2011
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G..G..G..Granville.........!! Fetch your cloth.
From his previous thread it looks like the machine s/n is 11K4920.
Good spot. I missed that.

In that case it falls into the group of machines between 11K3919-5050 which is the earliest group of 977L machines that were built. Machines up to 11K3918 were badged as 977K models.

If it is original the engine is NOT a 3306, it is a D333 and will be a pre-combustion chamber engine. The way to check the engine type is to look for the Serial Number plate on the cylinder block. If the S/N on it is the same as the machine then it is original and the engine is definitely a D333.

My best suggestion to identify any engine parts would be to get hold of the appropriate Parts Manual. Caterpillar Publication reference UEG0584S covers machines with S/N between 11K3919 and 5050. Plenty of used ones for sale on eBay priced from $30-up.
 
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tctractors

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Worc U.K.
The early series 3306 engines are all P.C. engines needing heat plugs to start, the no water thing is an old issue and most probably the reason of selling the shovel, if the head is off and no cracks are visible within the cylinder space and the bore's look good you are in with a chance of just stripping the chambers then re-setting them with new gaskets and O rings, you will need to strip out the coolers to clean out the water tubes also.
 

JohnnyAirtime

Active Member
Joined
Feb 23, 2017
Messages
37
Location
Alpine, CA
Good spot. I missed that.

In that case it falls into the group of machines between 11K3919-5050 which is the earliest group of 977L machines that were built. Machines up to 11K3918 were badged as 977K models.

If it is original the engine is NOT a 3306, it is a D333 and will be a pre-combustion chamber engine. The way to check the engine type is to look for the Serial Number plate on the cylinder block. If the S/N on it is the same as the machine then it is original and the engine is definitely a D333.

My best suggestion to identify any engine parts would be to get hold of the appropriate Parts Manual. Caterpillar Publication reference UEG0584S covers machines with S/N between 11K3919 and 5050. Plenty of used ones for sale on eBay priced from $30-up.

Engine number is 11K1920

Body number is 11K4920
 

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JohnnyAirtime

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Feb 23, 2017
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Location
Alpine, CA
Thanks for all your insight thus far. Big help.
... since I'm so new to heavy equipment, it's a big learning curve. But, I'll learn quickly when it costs money! Either way... I'm back on this and spearheading it.


UPDATE....
At this point, I'm back from a vacay and going to take the head to a machine shop. I found one within' and hour from my house and talked to the owner. He's what I'd call a "good ol' boy". Speaks with an accent (East coast or Southern) and is older (above 60). So that's good news, that they're familiar with the 3306 and actually have a 3306 head from an international they just refurb'd.

So... once I drop it off... They'll test it (Magnaflux, pressure test, etc) and let me know it's condition.

Of course, they'll inspect the pre-cups and go through the necessary check lists to determine if the head or any part of it IS the problem for water in Cyl#1.

I'll update once the I get word on that test... be about a week from today.
My mechanic said we could service the pre-cups and torque them down... and put the head back on to see if it still leaks (new head gasket of course)... but, I'd rather have it tested to know for sure. He agreed, that it's a sure way to know if the head was hurt or not and go from there.
 
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JohnnyAirtime

Active Member
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Feb 23, 2017
Messages
37
Location
Alpine, CA
Actually because it is one of the earliest 977K models with an engine that predates the 3306, the engine Serial Number and the machine Serial Number will be the same - 11K4920.

You are correct.... I didn't zoom in on the engine plaquard. It is indeed a 4

When you say "predates", doesn't that mean it's NOT a 3306?

And... it's a 977L correct, even though serialized as an early model L? Or is it truly a "K"?

Oh boy... stuff you'all know is appreciated. I mean... "Bob" was who I always saw with this knowledge, but I don't see him on this forum anymore. Did we lose him??
 

Nige

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When you say "predates", doesn't that mean it's NOT a 3306?
I’ve been saying that right from the start. Please back and read Post #9 carefully.

And... it's a 977L correct, even though serialized as an early model L? Or is it truly a "K"?
It is an L, just a very early one. Again from Post #9 the first L built was machine S/N 11K3919.
I wrote 977K in Post #14 above where I should have put 977L. My apologies for that mistake.

"Bob" was who I always saw with this knowledge, but I don't see him on this forum anymore. Did we lose him??
If you are referring to Bob/Ont who was very knowledgeable on this line of machines then he passed away a few years ago.
 

Old Magnet

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Corralitos, California
This always seems to throw everyone....the engine is actually a D333c (4-3/4" bore), forerunner to the 3306. Check for an all cast water pump. A 3306 water pump will have a large rectangular cover plate.
 

JohnnyAirtime

Active Member
Joined
Feb 23, 2017
Messages
37
Location
Alpine, CA
Interesting info... thank you all.

I do have a operators, service, and parts manuals/diagrams. Bought them on eBay as a thumbdrive. Not the best or easiest to see/read, but I figured easier since I'm more a computer guy than a mechanic I could use the 'search' feature since they're PDFs. In hindsight, I should have bought the thick "book" style. Just as my mechanic suggested.

I take the head in tomorrow to the machine shop... *fingers crossed*
 
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