Mercury Kg7h Good Deal?

[Kentfielddude]

IMG_0620.JPG 00A0A_eTOvzHmDSbV_600x450.jpg 00X0X_cNuBAsXjKE_600x450.jpg 00i0i_ikoQYkjmNJZ_600x450.jpg I want to buy a Mercury kg7q or h for my boat. I found a guys selling one for $1250 and was wondering if it was a good deal. He thinks it's a kg7h but the factory plate is marked kg7. This makes me think It may be a kg7q. Does anyone know what model this mercury is or how to figure out if its a q because I know some weren't marked.

[Herb Lanphear]

It is a KG7 tank band and tank on an H tower, the powerhead is probably a KG7 but could be a lot of things, not a factory H motor but looks like a pretty nice engine, not too bad a price but a 1000.00 would be better. Good Luck!

[squirrelboydeluxe]

Not a true H motor. It is a kg7 fishing motor on an H tower (& foot).
The real value here is the tower & foot; probably worth the asking price.
A real H motor would have "H" on the mfg tag & stamped on the block- just after the ser#
A Q (tower) is approx. 3in longer than an H tower & has an additional cav plate
A true "Q" motor will either have a Q stamped on the tag (early version) or silk screened (late version)
Even earlier models had "HD" (heavy duty) stamped on the tag; these are very rare

Did you say your boat is eleven feet? If so, this motor will certainly work (just okay) but you are likely to need more motor
Another thing to consider is the earlier KG's had Bendix/Scintilla ignition...dump truck loads of hair have been ripped out of otherwise good skulls fussing with these obstinate troublesome ignitions

Here is question #1 for your seller- DOES IT RUN?
"Well, the guy I bought it from said it runs."

Question #2: HAVE YOU EVER HEARD IT RUN?
"Um no"

The list of parts incl is a whole lot of fluff. The only things I see worthy of note are the coils & impeller.
I would much rather see an invoice from the foot doctor verifying the foot is sound.

Welcome to the agony of vintage motors...GB

[dwhitford]

I think as the older guy, I might be the authority here. The engine is on an original ''Q'' type, 15'' driveshaft housing, which is worth extra collector bucks in its own right, provided that the driveshaft within is original and not a shortened (H-type . . .?) with coupler. The coupler mod can work fine in regular service. What we're debating here is collectability.

I think you can find a serviceable engine for your (play-racer )? . . . use far cheaper than this questionably collectible KG-7. The KG-7 in question, however, is quite a nice example, especially with both its bottom cowls, which usually go missing.

[dwhitford]

I made a mistake, sorry. A closer look at your pictures disclosed that the tower (driveshaft) housing is the shorter H tower. The Q tower was the first ''Quicksilver'' tower and of a design length to work on standard fifteen-inch ''fishing-boat'' transoms. The H tower came later for ''hydros'' to lower the center of gravity, two inches shorter if I'm not mistaken.

Although the Merc Factory did produce some complete KG-4H (15 cubic inch A-Class) engines starting in 1953 or '54 (I think), I believe I'm correct in saying that the factory never produced any KG-7H or KG-7Q engines. The entire idea about Stock racing Mercs in the early 1950s was that you could buy (for about $200) the new Q (at first) or H (later) driveshaft housing and racing gearfoot and attach it to your fishing engine by simply unscrewing 6 nuts, adding a new gasket, and screwing the new lower unit assembly onto your fishing-engine powerhead. Except for the clamp-bracket assembly, it was an easy enough DIY project for many racers of that era.

But some racers elected to have their Merc dealers do the work. Authorized Merc dealers were allowed by Merc to stamp a Q or H onto the model name of the tank ring. Not all dealers did so. And for the DIY racers, this step was also commonly omitted. So finding a KG-7 with a correctly stamped Q or H is far less likely than finding an unstamped KG-7.

The Mark 20 of 1953-'55 is basically a KG-7 with a pressure-feed carburetor on it to replace the gravity-feed carb of the previous engine. And the Mark 25 is basically a Mark 20 with a beefed-up crankshaft and crankcase assembly and a fuel pump to replace the pressure-feed system. Either will bolt onto a Quicksilver racing lower-unit assembly and at a far cheaper price than a collector-grade KG-7. While the Mark 20 still had the dread Bendix-Scintilla ignition on it, the Mark 25 shares the less troublesome Phelon ignition of the Mark 20H, and Phelon-compatible points, coils, and condensers are still available from Sierra.

So either a Mark 20 or Mark 25 could work well for you. I think the 22 cubic-inch Mark 28 and Mark 28A engines also share the same powerhead-to-driveshaft-housing bolt-up pattern , , , not dead sure about that.

The big part of the expense will be the racing lower unit. Don't be surprised to discover that this could cost $500-600 or more in today's money.

I don't do private messages well on this site, but I think I've answered here your question about a suitable engine for your boat-resto project.

[ZUL8TR]

Not a true KG7H, a service powerhead on an H tower. Can't read what's on the paper.

If you want an original vintage look these old boys are the ticket but be prepared for repairs that may be needed once in your hands. Especially the gear case that are the expensive part and costly to fix if in bad shape which you do not know the condition of. Me I would never by an old engine without personally inspecting it too many unknowns. Also as noted above the ignitions on these are a PITA - been there. If you want an engine that will get you across the lake and back you might consider a different one although this is a clean looking one. I would look for a an engine that you interview actually running. Personally I would like a 20H (without the conversion popper exhaust to keep the neighbors happy) but they are costly in great shape.

These engines need some special tools to work on if you are a DIY'er, if not it can be expensive to get it done. Some parts are not so easy to get, some are gone forever .

[3autility]

I recently bought a KG7 on an H tower for $250. Guess I stole it. Motor is in nice shape. Just rebuilt the Scintilla mag. Has great spark. Can also change to a Phelon if I need to, since I have a set up. Next will be bottom crankcase seal. already did the top.

[Kentfielddude]

3autility you sniped that engine for that price! Thx for all the help dwhitford.

[Kentfielddude]

Found two Mark 25 for sale. Both are in running condition: http://appleton.craigslist.org/bpo/5782692211.html
http://madison.craigslist.org/bpo/5787346503.html

[3autility]

Correct me if I am wrong, but weren't KG7Hs just the same as a KG7 but on a racing lower unit? I would say if you could get it for about $1000 you would do well. If I were to sell any of my KG7Hs that is about what I would ask, but if he sticks with $1250 take it and have fun with the motor. It looks pretty good, but who knows about internals etc.
Chuck Webster

[Kentfielddude]

He sold it to someone else.

[jeff55v]

Umpteen years ago, I owned a KG7H. It had the H stamped on the tank and block, and the H tower and foot. I took the powerhead apart to look for differences between an H and service motor. The only difference I could find was that the spark advance lever had a notch in it, to allow for more travel and more spark advance.
But perhaps this was a mod done by a previous owner.
In my opinion,in this day and age, a nice green top Merc belongs in a collectors display.

[trident]

I had a genuine KG7H back in the day... as a play motor. Paid $60 for it from a local dealer in the early 1960's, as it was obsolete for any racing... came with a steering bar and a brass Kamic prop.

It had the H stamped on the plate, the H short tower and gearcase, the Scintilla mag with a factory lightened thin flywheel and an AJ 32A carb without the bump. Ran really well on an old Swift hydro. And, it was the first motor I ever ported, by hand, with jewelers files. Actually picked it up good bit...

I put a KG4 tank rim on it, so it looked like an A at first glance... Like I said, a play motor.

Also had a KG7Q prior to that, a stock service KG7 powerhead on the longer Quicky unit. Good runner, first motor I ever bought. Got it really cheap from the local Evinrude dealer who had trouble selling it. It sat and sat. I gave him $35 for it in 1958. I was thrilled to get it! I never went so fast on water... I like this!

[johnsonm50]

Here's some things to consider: Your boat, is it a flat bottom runabout or hydroplane type race boat? That's what these small Merc race motors are for & might not deliver well on a V or keel type boat. You, are you light enough to run an A or B sized boat? Speed, do you have experience in this type craft. The reason I asked the last Q isn't because of doubt in you but whether or not you'll be satisfied after parting with a good amount of cash. If you post pics & write a bit more about what you're working with you'll likely get more good advise specific to what you're doing. Good Luck

[Kentfielddude]

This is the boat I'm looking to find an engine for: 11' 3" paid $80 for it. s-l1600 (1).jpg

[Fastjack]

looks like a Hal Kelly --- Blue Streak---

[johnsonm50]

From what I've seen of Hal Kelly designs they did vary enough to include this but I'd guess early if so. There were several popular ones, Foo-ling, Airborne, Jinx, & Madcap to name a few.

[johnsonm50]

The price was right. It's a cool looking utility runabout but I don't recognize the make, it looks to be flat bottomed where it counts, does it have a keel or a turn fin [or place one was screwed in on the port side a few feet from the transom]? It looks like the transom was at one time 15" for a standard 'short' motor. That opens your choice range to many fishing type motors as well as some racers. Questions being how would the boat handle at 45-48 mph & would it be sound with more. At 11'3" it's probably a B utility.

[Bob Rusnak]

I had the same boat, It was a kit boat maybe from Science $ Mechanics. I bought it already built. Had a lot of fun with it. Put a Mercury MK 25 on it and later a Mercury KG7. The speed was not far off between the two engines.