165 hp Chevy Stovebolt Inline 6, 37 Yrs old

[zetalampi999]

I just recently bought this boat '72 AristoCraft Nineteen. I love the looks of the boat and it cleaned up great. I imagine that most of the engine is original, and it starts up right away and runs strong.

It seems to be running hot when at higher speeds and at one time the temp guage read over 250 degrees F. I slowed to an idle and beat on the guage hoping that it was stuck, it did move down a little to maybe 240 then slowly came down to around 170-190 and just wanted to stay there. I brought the boating to an end early. I tested the impeller from the lower unit and it is pumping large volumes of water. I will look at the Thermostat next followed by the the exhaust manifold to look for blockage.

Does it seem like im on the right track, anything else to look for? What is the normal operating temperature for this engine? Also what are your opinions on this engine's durability?

 

[ziggy]

Re: 165 hp Chevy Stovebolt Inline 6, 37 Yrs old

looks like ya got a winner to me... i suppose i could be prejudice though....
yep, yer getting to hot. normal operating temp should be between 140 and 160, assuming rwc (raw water cooled, not closed w/ a heat exchanger). the tstat should be a 140. if ya put the tstat in a pan of water and bring the temp up. you'll see it start to open at 140 and be full open at 160. usually the tstat isn't the overheat problem. could be, but not usually.
you may think you've got good flow. but the first place to look for a overheat is the impeller. R&R it on general principles. you'r suppose to inspect it once a season. they're not real easy to go look at, so when ya do, ya might as well R&R it. do the housing too, at least on the first time 'you' change it. also, assuming the impeller is in pieces. go find as many of the pieces that you can find. also, check your water hose that goes between the bellhousing and the gimble housing. sometimes that hose can get a kink. this impeeds water flow if ya got the kink. there are other possibilities too, including the manifold and riser.
to me, a real good artical is the summerization thread in the adults only sticky thread at the top of the i/o page. this is a good place to start as to getting your boat ready to go. there's lots of items to check out and ya should probaby check them all. in that same thread, you can find the oem service manual. it will become your best tool in the tool box. it has the facts in it. assuming it's a mercriser of course.

if your not hip yet. go to www.aristocraftboats.com there you'll find a phone number to the oem. well, the oem's grandson i believe. he may have brand new parts for your boat depending on what you need. obviously, not everything is still available, but for a 37 year old boat, it's amazing any parts are available brand new. i've gotten a blower, center windshield panel, hardtop slides. seems like i got some other stuff, but can't remember.

you'll like the mercruiser 165hp L6. they're a good engine. i've heard them described as one of the best engines for marine use there ever was. i doubt you'll ever find anyone that don't like the mercrusier marinized, chevy 250.

congrats on your new boat man..... my guess is your gonna like it a lot... i sure do mine....

might go to the aristocraft fourm here on iboats too. there's getting to be a few of us that are hip... some interesting reading in there too. i think. but like i said, i think i could be prejudice...

 

[thefishinguy]

Re: 165 hp Chevy Stovebolt Inline 6, 37 Yrs old

good choice on boat/ motor purchase. I run an inline 6 commercially eveyday with 3,143 hours on the omtor and thats just sine 1999 i don't know what it had for hours previous to the rebuild at that point.

But in terms of heating. if its fresh water coold(half closed) clean the heat exchanger. They get pretty clogged up over time. if its raw water cooled take everything off the block that has water running through it (after checking for a stuck thermo/ bad hoses) and make sure all passages are clear. lastly Change your gauge/sender. I've seen people go insane looking for and over heating problem when there wasn't one and it was sender/gauge problem. don't forget your talking in some cases about 30 somting yr old parts here....

Good luck that motor won't let you down, I've gone 20 miles on 3 cylinders to get home before and shes still going.