lost of power going up hill

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dlb
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My tercel:: '87 sr5, '83 dlx parts car
Location: bc, canada

Re: lost of power going up hill

Post by dlb »

your fuel filter looks like one of these plastic guys:

http://www.partstrain.com/ShopByDepartm ... ERCEL/1981

and it's near the battery, just a little closer to the firewall--the firewall is the wall between the engine bay and the dashboard. it's super easy to change, just pull off the two hoses and pull the old filter out. put the new one in and hook up the hoses. there are arrows on the filter to tell you which hose goes on where. remember that the fuel needs to flow from the fuel tank at the back of the car through the filter and up to the carb.

you need a compression tester to check the compression. get one from a parts place for $20. then you remove the wires from all of the spark plugs, take out one plug at a time, put the tester in and then crank the engine 8-10 times. put the plug back in and move on to the next one until you've tested all four cylinders. write them down as you go. a new engine will have about 180 PSI compression on each cylinder and a worn engine will be around 120 PSI on each one. less than 120 means your rings need replacing, which is a big job. if all cylinders are somewhere between 120 and 180 and within 10% of each other (140, 135, 145, 132) you're fine. if one ore more cylinders is way lower (150, 155, 80, 144) you probably have a damaged valve in the head.
Highlander
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Re: lost of power going up hill

Post by Highlander »

NO, NO, NO. Do NOT do a compression test with the plugs in! ALWAYS run a compression test with all of the plugs out, and the throttle plate wide open. The draw on the battery of cranking repeatedly with plugs in, will reduce the spin rate for each successive cylinder, giving you false low readings on the last cylinders tested. If you leave the throttle plate closed, then the cylinder that you're testing has to pull against a restriction, limiting the amount of air in the cylinder again resulting in false low readings. Shade tree mechanics (read un-schooled, not DIYers) will often sell engine repairs based on the poor results of improper compression tests. Caveat Emptor!
'83 SR5-299K, -tRusty!
'85 SR5-265K--GOLD
'85 SR5-285K-- GOLD-New engine!
'85 SR5-238K -- Teal-Killed by a DD
'58 and '62 Austin-Healey Sprites
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dlb
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My tercel:: '87 sr5, '83 dlx parts car
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Re: lost of power going up hill

Post by dlb »

highlander, as long as the spark plug leads are all detached, there shouldn't be much draw on the battery, no? i wrote how i have always checked compression and haven't had any problems but i could still be wrong so i want to check.
toughtercel
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My tercel:: 83 4WD with some SR5 equip
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Re: lost of power going up hill

Post by toughtercel »

How long you own this car , If you are new driver then it a 62 HP car . How old and thick is your motor oil while driving this car , lubraction is important to keep the motor healthy .
Highlander
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Re: lost of power going up hill

Post by Highlander »

Sorry Dave,
But the idea is consistency, any time you draw the battery down, it'll affect the crank rate. Repeated cranking without voltage input will reduce cranking speed. The more resistance there is to the starter, the more current it draws, the more current it draws, the less capacity in the battery, the lower the Voltage (V=I*R) to turn the starter, the slower the starter turns, etc, etc.
The other problem with leaving the plugs in is that the compression in the other cylinders slows the crank rate at variable amounts depending on what the compression is in those cylinders, pulling the plugs and opening the throttle plate (Choke plate too) removes any cross talk and restrictions in the flow path giving you the best possible chance at seeing an (almost) real value for the compression pressure.
It's more a question of limiting the variables between the cylinder readings, so you want to keep as much as possible the same. Any impediments to the air flow will show up as a lower compression pressure.
As you might expect, valve overlap and lash adjustment also can play a part since they control the opening and closing points of the valves. Now this is probably more applicable to someone looking for as much power or torque as possible (i.e. racers), but why chance it? When in doubt, I always do things the most consistent way to achieve the best, most consistent results, anything else, IMHO, is a waste of time-then if you have to do it over again, you should achieve similar results.
'83 SR5-299K, -tRusty!
'85 SR5-265K--GOLD
'85 SR5-285K-- GOLD-New engine!
'85 SR5-238K -- Teal-Killed by a DD
'58 and '62 Austin-Healey Sprites
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dlb
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My tercel:: '87 sr5, '83 dlx parts car
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Re: lost of power going up hill

Post by dlb »

this is excellent info, thanks HL!
lakkham
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My tercel:: 84 toyota tercel SR5 4WD

Re: lost of power going up hill

Post by lakkham »

ok..i found the problem...thanks guys..it was the clutch it just went out...
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Petros
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Re: lost of power going up hill

Post by Petros »

you did not mention the rpms would rise when you "lose power". I suspect you would have also smelled the clutch too. But clutches can go bad fairly quickly, one week is fine, and 3-4 days after first symptom it becomes undrivable.
'87 Tercel 4wd SR5 (current engine swap project)
'84 Tercel 4wd (daily driver, with on going mods)
'92 Mazda MPV 4wd (wife's daily driver)
'85 Tercel 4wd DLX auto(daughter's daily driver)
'01 Honda Civic (other daughter's daily driver)
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