Clutch problems

shawtech · 04-22-2009, 02:04 PM

Clutch problems
Ok so I have the motor going fine took a little bit but its sounding good..... Problem,,, I have little to no back pressure on the clutch ... I’m thinking I need to bleed the master cylinder and re-prime??? Does anyone know how to troubleshoot this dilemma...?

tjmr2 · 04-22-2009, 04:42 PM

First I'd make sure the slave cylinder is properly mounted and moving the release fork in the transmission. Your resistance to the pedal and return are mostly controlled by the clutch pressure plate springs.

If the slave cylinder isn't moving the release fork you may have air in your hydraulic line or a bad slave or master cylinder. You will have to jack up the car and have someone push on the clutch to see if the slave cylinder is moving the fork.

Check the fork and see if it's tight in the transmission and doesn't have a bunch of play.

Make sure you have fluid in the reservoir in the frunk, then have someone help you bleed the system from the slave cylinder. I used a vacuum brake line bleed kit from Harbor Freight and did it without help.

Keep us posted.

shawtech · 04-23-2009, 11:57 AM

i have put "marvel mystery oil down the cylinders and into the oil reservoir, all ignition components, coil, distributor, all sparking, the intake is super clean, washed out the throttle body... but im not sure of my injectors??? the exhaust manifold is bolted up nice and i fabricated my own throttle bracket.. all electrical systems work however the front headlights do not lift and retract.... that's all of what i have going now ... along with the clutch ... thank you TJMR2

tjmr2 · 04-24-2009, 12:59 AM

You are welcome.

When I rebuilt my 1.6 years ago I took the injectors to a shop in Greeley (I was living in Windsor) they had a machine and the chemicals to flush them out and test them. Think it cost me $10.00 or so each. The engine had 115k so I figured it would be worth it.

Have you been able to download a copy of the BGB? I don't know if the online copy has the electrical schematic. The Retract control Relay is fed power from a 30A RTR fuse (pin 3) and a 7.5A RTR fuse (pin 10), and gets it's signal to lift and retract when the headlights come on thru pin 6 and when you flash your lights pin 8.

The head lamps themselves get power from the headlight relay. Pins 4-5 are the switching contacts, 5 hot, 4 to lamps. Pins 1-3, (3 is hot) are the coil.

Hope this isn't too confusing and it helps.

lsgheero · 04-24-2009, 11:54 AM

If the clutch and master cyls are bad don't buy new ones just get a rebuild kit much cheaper and rebuilding only takes about 3 mins once you have them out of the car lol. I recently redid mine took about 3 hours but that was because it took forever to get the master cyl out lol very tiny space to work in and I have big hands lol.

mr2tim · 04-25-2009, 03:20 PM

The cylindrical connectors in the front headlight harness are engineered defective. Here's some photos to check out your problem.

Might check the grounds too, it's just this tiny screw and an eyelet.

BTW relays seldom fail.

Also here's a picture of the clutch adjusting mechanism at the footpedals.

mr2tim

shawtech · 04-26-2009, 10:01 PM

you guies are the best!!

toyotaspeed90 · 04-29-2009, 04:27 PM

if you don't have return pressure... is that all the time or only if you hold your foot on the clutch for a given amount of time?

Early Mr2's have cast iron master cylinders --- which after time the water absorbed into the fluid will pit the cylinder of the master cylinder -- so it's quite common for Toyotas with cast cylinders to feel ok going in, but the fluid actually gets trapped in the walls of the cylinder, and when you pull back the seal actually seals better going backwards and pulls fluid into the cab.

If this is the case, order a new one -- DO NOT REBUILD because you will have the same problem shorty after. When you do order one, order a Clutch master cylinder for an 89 -- that way to ensure you get the better aluminum pieces that don't pit.

04-22-2009, 02:04 PM	#1 (permalink)
shawtech aeronautical engineer Join Date: Feb 2009 Location: Boulder , CO/ Quani , RI Posts: 47 Thanks: 0 Thanked 0 Times in 0 Posts iTrader Rating: (0/0% )	Clutch problems Clutch problems Ok so I have the motor going fine took a little bit but its sounding good..... Problem,,, I have little to no back pressure on the clutch ... I’m thinking I need to bleed the master cylinder and re-prime??? Does anyone know how to troubleshoot this dilemma...?

04-25-2009, 03:20 PM	#6 (permalink)
mr2tim SUPERcharZed ToyZ RacZer Join Date: Mar 2008 Location: South Florida Posts: 1,789 Thanks: 8 Thanked 118 Times in 111 Posts My Google Map iTrader Rating: (6/100% )	Headlight pop-ups & clutch adjustin' The cylindrical connectors in the front headlight harness are engineered defective. Here's some photos to check out your problem. Might check the grounds too, it's just this tiny screw and an eyelet. BTW relays seldom fail. Also here's a picture of the clutch adjusting mechanism at the footpedals. mr2tim Attached Thumbnails

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04-22-2009, 04:42 PM	#2 (permalink)
tjmr2 Cage Fighter Join Date: Jan 2008 Location: Colorado Posts: 409 Thanks: 0 Thanked 62 Times in 59 Posts My Google Map iTrader Rating: (0/0% )	First I'd make sure the slave cylinder is properly mounted and moving the release fork in the transmission. Your resistance to the pedal and return are mostly controlled by the clutch pressure plate springs. If the slave cylinder isn't moving the release fork you may have air in your hydraulic line or a bad slave or master cylinder. You will have to jack up the car and have someone push on the clutch to see if the slave cylinder is moving the fork. Check the fork and see if it's tight in the transmission and doesn't have a bunch of play. Make sure you have fluid in the reservoir in the frunk, then have someone help you bleed the system from the slave cylinder. I used a vacuum brake line bleed kit from Harbor Freight and did it without help. Keep us posted.

04-23-2009, 11:57 AM	#3 (permalink)
shawtech aeronautical engineer Join Date: Feb 2009 Location: Boulder , CO/ Quani , RI Posts: 47 Thanks: 0 Thanked 0 Times in 0 Posts iTrader Rating: (0/0% )	i have put "marvel mystery oil down the cylinders and into the oil reservoir, all ignition components, coil, distributor, all sparking, the intake is super clean, washed out the throttle body... but im not sure of my injectors??? the exhaust manifold is bolted up nice and i fabricated my own throttle bracket.. all electrical systems work however the front headlights do not lift and retract.... that's all of what i have going now ... along with the clutch ... thank you TJMR2

04-24-2009, 12:59 AM	#4 (permalink)
tjmr2 Cage Fighter Join Date: Jan 2008 Location: Colorado Posts: 409 Thanks: 0 Thanked 62 Times in 59 Posts My Google Map iTrader Rating: (0/0% )	You are welcome. When I rebuilt my 1.6 years ago I took the injectors to a shop in Greeley (I was living in Windsor) they had a machine and the chemicals to flush them out and test them. Think it cost me $10.00 or so each. The engine had 115k so I figured it would be worth it. Have you been able to download a copy of the BGB? I don't know if the online copy has the electrical schematic. The Retract control Relay is fed power from a 30A RTR fuse (pin 3) and a 7.5A RTR fuse (pin 10), and gets it's signal to lift and retract when the headlights come on thru pin 6 and when you flash your lights pin 8. The head lamps themselves get power from the headlight relay. Pins 4-5 are the switching contacts, 5 hot, 4 to lamps. Pins 1-3, (3 is hot) are the coil. Hope this isn't too confusing and it helps.

04-24-2009, 11:54 AM	#5 (permalink)
lsgheero RAR! Join Date: Feb 2007 Location: Arizona Posts: 747 Thanks: 9 Thanked 31 Times in 31 Posts My Google Map iTrader Rating: (1/100% )	If the clutch and master cyls are bad don't buy new ones just get a rebuild kit much cheaper and rebuilding only takes about 3 mins once you have them out of the car lol. I recently redid mine took about 3 hours but that was because it took forever to get the master cyl out lol very tiny space to work in and I have big hands lol.

04-26-2009, 10:01 PM	#7 (permalink)
shawtech aeronautical engineer Join Date: Feb 2009 Location: Boulder , CO/ Quani , RI Posts: 47 Thanks: 0 Thanked 0 Times in 0 Posts iTrader Rating: (0/0% )	you guies are the best!!

04-29-2009, 04:27 PM	#8 (permalink)
toyotaspeed90 No Skills Join Date: Jun 2006 Location: Bellingham, WA Posts: 2,401 Thanks: 0 Thanked 148 Times in 143 Posts My Google Map iTrader Rating: (0/0% )	if you don't have return pressure... is that all the time or only if you hold your foot on the clutch for a given amount of time? Early Mr2's have cast iron master cylinders --- which after time the water absorbed into the fluid will pit the cylinder of the master cylinder -- so it's quite common for Toyotas with cast cylinders to feel ok going in, but the fluid actually gets trapped in the walls of the cylinder, and when you pull back the seal actually seals better going backwards and pulls fluid into the cab. If this is the case, order a new one -- DO NOT REBUILD because you will have the same problem shorty after. When you do order one, order a Clutch master cylinder for an 89 -- that way to ensure you get the better aluminum pieces that don't pit.