mercruiser motor question

[Fishtails]

I have twin mercruiser 165's (inline 6) powering my boat and I have a chance to buy a completely rebuilt 165 that is a pan to carb plug and play motor. The two motors I have both run solid with perfect compression, but one needs a valve guide, engine coupler and the exhaust manifold is a little leaky. I'm thinking of buying this rebuild and pulling the one that needs repairs....then having that rebuilt eventually to replace the second.

The boat shop is asking $1400, but said they'd take $1250 for the motor. Does that sound like a fair price for a no trade-pan to carb complete 165 ?

[borderline 350]

Dear F.T,

These early 250 cubic inch 6 cylinder motors are scarce and old. They were a very fuel thrifty motor. Yes the Mercruiser original exhaust manifolds were made of aluminum and earned their reputation for leaks! Replacements are available in cast iron. Watch out, the ignition distributors had a habit of tearing up the top bushing and losing their point gap! The gap should be .016 to .019 inches to achieve a dwell reading of 32 degrees. If this is not possible, it's bushing/rebuild time.

But let's get to your question on value. Yes a rebuilt 165/250 engine is worth all of $1250 outright. Be sure you get some kind of guarantee from the marina. It would be nice to know who did the actual rebuild and what was replaced. This will set your mind at ease and give some faith in your equipment! Actual cost of a good rebuild including assembly will easily surpass 1250!

Remember that these engines were designed to run on leaded gasoline, so running them on unleaded fuel will cause early valve seat and valve erosion! This problem can be solved by having stellite valve seats installed by a professional cylinder head builder.

Sincerely,

Jet Boat bill

(P.S. My first boat (19 PennYann) had a 165/250 6 cylinder and was the best boat on fuel that I have ever owned!)

[Fishtails]

Thanks for the input Bill, I appriciate your advice. I spoke with Cook's (who are doing my repairs) and they agreed that it sounds like a good plan and a fair price. I am picking the motor up on Friday from a boat dealer in Maryland.

Both of my current motors have been converted to the electrinic ignition, as well as the new one. I ran these 165's for the entire season last year without any problems and I really like them. I think my gas consumpion on my 24 ft Searay with twin's is not much worse for a day of trolling than my 19 ft Lund was with a merc. 90 outboard.....seriously.

[L&M]

Maryland? Is it a salt water engine to start with? What Bill said is very valid and good advice for a fresh water engine, price as well. But now your throwing an other equation into it. How old and or what year is the engine? Was it run in salt water all the time and if so for how long?

[Fishtails]

Hank,

Does it matter if it was a saltwater motor prior to it's rebuild? Being from Maryland, I'm sure it probably was. I did not ask this question, but I'm told the motor is still in it's break in period with only a few hours and has been rebuilt top to bottom. It's at a boat dealer who had bought a pair of them for another project, but for whatever reason they have not gotten to it. He sold one and has one left.

Here is the picture he sent me....I'm going to look at it on Thursday.

Anything I should look for....or be concerned about? I'm told the compression is good and equal in all 6 cyl.

I've never bought a motor like this that wasn't in a boat. Can we start and run it out of the boat?

Thanks for the help guys!!

[L&M]

Rod: Sent you a pm.

[borderline 350]

Dear F.T.

Salt Water use in raw water cooled engines such as this keep us engine guys very busy! Inspect inside the oil filler hole with a flashlight and look for small puddles of water or rust. Pull the dipstick out and examine the oil color closely! If the engine is running properly, the oil color will be CLEAR! If any cloudiness or yellow color is present, it's a good bet that you have an internal water leak! Get something in writing regarding.."No internal water leaks during first 30 days of OPERATION! You have been warned!.... Take a small magnet with you and be sure that the welch plugs in the block are non-magnetic. Scratch the paint off a little and be sure you see brass. If not, walk away. Look closely at the oil pan and be sure that large areas are not heavily corroded and painted over. A little caution and examination are very important before the money changes hands. ....The motor can be run as it is with a little work and a small support stand for the back. But it takes some engine smarts to hook up fuel, water and ignition w/o damaging the alternator etc.

Good luck with your quest!... Jet Boat Bill

[Fishtails]

Thanks again Bill....between your advise and Hank's, I think I will be able to make an informed decision when I see it on Thursday.

[Fishtails]

Thanks again for the help Bill & Hank. Everything seemed to check out ok per your suggestions, so I bought the motor today. Hopefully if this weather holds a little longer I'll get it installed sooner than later.

[L&M]

Not a problem Rod. Hope it works out ok for ya. Did you find out where it originally came from?

[Fishtails]

He didn't really know Hank, but he bought it from another local marine shop. I fugure now I have three good motors and I only need two, so I should be ready if anything unexpected pops up. I hope to make the swap later in the week ??

[Rich D]

Rod,

If you were closer I would give you a hand swapping out the motors. Get her ready, spring is coming. Good Luck with the swap.

Rich

[Fishtails]

Thanks Rich.....that's cool of you to offer. I had the boat at Don Cooks up till a couple days ago. We decided that since I like this boat, we'd give it a good going over. Cook's has both outdrives and they are refreshing both of them. To save a few bucks, they suggested I do the engine swap myself and then take it back for them to finish it up. While I'm at it, I'm pulling the other motor also to replace that coupler as well.

You know how it goes Rich, once you get started you uncover all kinds of things that could use replacing. Might as well just get it done! She should be running like a top by early April!

I can't wait till spring!! I'm hoping to be out west a big chunk of May.

[borderline 350]

Dear FishTails,

I have something you may be interested in. A complete 1980 OEM Mercruiser Stern drive units and Marine Engine manual with supplement. $35.00 plus shipping if you are interested. The manual contains great stuff including electrical diagrams, pictures, engine component overhaul, Merc I drives and more. I am putting it up for sale today....

Sincerely,

Jet Boat Bill

[Fishtails]

You have a pm Bill

[Fishtails]

Hank and Bill.....I just thought I'd follow up and tell ya guys I got the new motor in today and go it running. Everything went pretty smooth and she fired right up for me. I found the water shutter to be missing, so I have to order that. Also, before I take it off the hoist, I was curious If those leather washers were still available? If so, should I replace them with new ones?? The old washers are intact, but they look a little crappy.

Then, as long as this weather holds out...it's on to motor number two .

Either way....thanks for the help guys!

[L&M]

Rod: If your talking on the transom plate with two longer bolts. Yes re place them as well as the springs in between. They are inexpensive and just good insurance is all, for the few $'s they are, you don't want to have to pull it again to replace them or have to replace a coupler because of it. On the same note MAKE sure that the engines are aligned before the drives are put back on.

[borderline 350]

Dear F.T.

As long as the coils are straight and no evidence of being deformed or taken a set is present, you could reuse them. The brown fiber washers should be replaced. If you could get new springs, that would be great also. REMEMBER that the mount bolts that go thru these parts must be torqued to (45 ft. lbs.??) FROM MEMORY. Look in your Mercruiser Manual and it will give the correct torque. also remember that you are working with a Mercruiser I drive which came before the Mercruiser Alpha drive. I will try to look up the P.N.'s for those parts tonight

Sincerely,

Jet Boat Bill

[Fishtails]

You know, come to think of it there were no springs when I removed the motor.....only the fiber washers and maybe a regular or lock washer :shock: . I have the parts in a container so I'll have to look in the am. Hope I can purchase them somewhere?

I'm not doing the alignment.....Don Cook has the outdrives and he is going to do the alignment for me when he puts the drives back on. I'm just doing the motor swap and coupler.

[borderline 350]

Dear FT,

I found what I believe are the correct PN,s

12-32834 and 13-33734A1 (Two each per engine) The two coil lock washer and fiber washer go underneath each of the bell housing ears. (On top of the inner transom plate mount ears). get this right otherwise the new couplers will fail very SOON! Putting the proper torque on the 5/8 head bolt establishes the vertical alignment of the engine at the rear only. The front mount adjustment establishes the final horizontal and vertical alignment. Do this while the engine is on a hoist with the alignment tool thru the gimbal bearing and into the coupler. This shortens the time & effort to properly align the engine to the gimbal bearing.

sincerely, Jet Boat Bill

P.S. That coil spring looks like a lock washer but has two coils!

These parts are approx. 1.75 each. These will be the cheapest parts that you ever will buy from Mercruiser!!!

[Fishtails]

Thank You Bill, I will follow your advise. I did go check and the spring washers are there, they were inside the washer hole....making it appear as though it was part of the washer.

I'm going to replace everything though If I can find some new ones.