| Re: Head gasket leak? [message #328565 is a reply to message #328252] |
Wed, 24 January 2018 09:46   |
JohnL455
Messages: 4447
Registered: October 2006
Location: Woodstock, IL
Karma: 12
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It's best to shift the trans manually going up and down hills. The kickdown is best left for passing maneuvers. You want to stay in the middle of the power band. By the time you were at 20 MPH you should have been in 1st gear. Keep a close eye on your oil and coolant levels at this time. Be sure your overflow has about 2/3 full of coolant. And watch gauges for normal ranges.
John Lebetski
Woodstock, IL
77 Eleganza II
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| Re: Head gasket leak? [message #328569 is a reply to message #328563] |
Wed, 24 January 2018 19:47 |
Ken Burton
Messages: 10030
Registered: January 2004
Location: Hebron, Indiana
Karma: 10
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Jimmy_Bonez wrote on Wed, 24 January 2018 09:23Thanks guys. Next oil change I'll take a look at changing the gasket. So far after tightening everything back up that was extremely loose, the oil drips have subsided to a reasonable amount. Now tho it seems like my "granny gear"(downshifting when going up hills or passing) is starting to struggle. It will downshift and kick the secondary on carb open only if I put my foot into the floor. We were coming out of Caprock canyon the other day and climbing a hill and I was nervous we weren't going to make it. We maxed out at 20mph any more Hill and we would have been crawling.
Common problem. I have fixed many of them. The throttle pedal rod gets bent from pressing too hard on it and the kick down switch is then out of adjustment.
With engine not running grab the accelerator pedal and pull up on it bending the rod about 1/2 inch towards you. That is it. You are done.
Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
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| Re: Head gasket leak? [message #328577 is a reply to message #328574] |
Thu, 25 January 2018 10:32 |
Larry
Messages: 2875
Registered: January 2004
Location: Menomonie, WI
Karma: 10
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shaunone wrote on Thu, 25 January 2018 08:20What John said. When your speed gets down to 45-50, drop it into 'S' manually 
Depending the final drive you are using (3.08, 3.21, 3.42, 3.50 3.70 or 4.10) 50 MPH may be be high or low in terms of engine RPM. Personally, I would use a 2400rpm rule. If you are at WOT and RPM drops to 2400rpm, that is the time to shift manually into "S"...or second. Then again when rpm drops to 2400, manually shift into first. For the 455 or 500, IMO, when climbing grade we should try to keep the rpm around 3000 or so. The 403 may run 500rpm or so higher. One must keep in mind what Dick Paterson has reminded us of, that because the oil pump runs off the the camshaft, it is turning at half the speed of the crank. Keeping rpm up keeps a good supply of oil going to the rod and main bearings under these high load conditions. So...just what I'd do.
Larry
78 Royale w/500 Caddy
Menomonie, WI.
[Updated on: Thu, 25 January 2018 10:33] Report message to a moderator |
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| Re: Head gasket leak? [message #328584 is a reply to message #328252] |
Thu, 25 January 2018 12:58 |
jhbridges
Messages: 8412
Registered: May 2011
Location: Braselton ga
Karma: -74
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Manny doesn't connect the kickdown for the 425, he says you're way better off to shift it manually. It will kick on RPM and load (Vacuum) but you're better off to hang it in low or 2 he says - higher line pressure to the clutches that way, less chance to slip.
--johnny
Foolish Carriage, 76 26' Eleganza(?) with beaucoup mods and add - ons.
Braselton, Ga.
I forgive them all, save those who hurt the dogs. They must answer to me in hell
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| Re: Head gasket leak? [message #328585 is a reply to message #328577] |
Thu, 25 January 2018 13:00 |
shaunone
Messages: 80
Registered: August 2016
Location: Cranbrook, B.C.
Karma: 0
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You're right Larry, thanks for clarifying. My general suggestion was for the bone stock guys like me (3.07 final and no tach). On paper, it looks like dropping into second at 45 puts the engine at 2350, and dropping at 50 puts it at 2600, so it looks like your rule fits my suggestion (unless I got the gear ratios wrong?).
1977 Palm Beach, 455, mostly stock and original
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| Re: Head gasket leak? [message #328601 is a reply to message #328584] |
Thu, 25 January 2018 18:45 |
Ken Burton
Messages: 10030
Registered: January 2004
Location: Hebron, Indiana
Karma: 10
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Manny connected mine when he built it and a couple of weeks after I installed it he sent me an improved kick down solenoid to replace the one I he had installed.
Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
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| Re: Head gasket leak? [message #328604 is a reply to message #328252] |
Thu, 25 January 2018 20:24 |
Jimmy_Bonez
Messages: 105
Registered: September 2017
Location: NH
Karma: 0
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Thanks for the responses again guys. I was very surprised at Kens response to bend the arm up a bit, only because I said to myself "I bet the gas peddle is bent but i shouldnt bend it back should I". I was wrong. So I did just that and it helped the situation a bit. I might be over examining every sound and rattle now that we've been on the road for the past 3 months. In all honesty I have never down shifted the coach manually (put it in S), I've never had to up until now we're started hitting the hills and canyons. Little nervous to break anything. We're in Albuquerque,NM now and headed thru more hills and canyons soon.
Jim DeMellia and Jen Radefeld and our cat Ickis
NH natives
1975 GMC “Palm Beach” ,455, her names Linda
Full time RVers exploring the beautiful and unusual parts of the country.
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| Re: Head gasket leak? [message #328610 is a reply to message #328604] |
Thu, 25 January 2018 22:05 |
Ken Burton
Messages: 10030
Registered: January 2004
Location: Hebron, Indiana
Karma: 10
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Senior Member |
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The kick down switch is located on the opposite end of that rod at the very top. By bending the bottom up it gives more travel on the top of the rod which operates the switch sooner. I have probably fixed 30 of them over the years that way. It takes less than 30 seconds to do it and requires no tools.
Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
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