Tdc

[Cochip]

I've done some searching here and haven't found exactly what I'm looking for. I've developed what appears to be a very common oil leak from the distributor o-ring. At first I thought this was being caused by the oil sending unit as I didn't use any teflon tape or thread sealant when I first installed it. I removed it and used a sealant, but the leaking has persisted and appears to have worsened. Upon further investigation it appears that the oil is coming from a source higher up on the block and I can't think what else it could be other then the dizzy o-ring. So here's my question. I've read on cygnus on how to set the #1 cylinder at TDC without removing the timing chain cover and it makes sense. What I'm wondering is how do you know for sure, after spotting the cam lobe through the oil cap location, that you've rotated the engine exactly 120 degrees back and then exactly 40 degrees forward without a degree wheel? I don't want to wreck my timing by not being able to tell how far I've rotated the engine. Is being approximate good enough here? I wouldn't think so, but the cygnus site makes me believe that is the case by offering this option to get to TDC. Is there any other way that works better? I'm tired of this oil leak and I'm hoping to get it square tomorrow. Thanks ahead of time all.

BTW: 1988 7MGE in a 1994 Toyota pickup

 

[AJ'S 88NA]

Just have to take the top cam gear cover off, line up the cam gears with the marks, pull the #1 spark plug to verify piston is at TDC, crank pulley is at "O", and the rotor is pointing at the #1 plug on the distributor cap.

Don't rotate the motor until you install the distributor back in.

 

[CyFi6]

If you don't want to remove the timing cover (requires that you drain the coolant) just rotate the crank until the notch on the crank pulley lines up with the 0 on the lower timing cover, then check if you can see the nose of the cam through the oil filler. If you can't, rotate the crank another 180 until the notch lines up with 0, and check that you can see the nose of the cam now. Now you will be at #1 TDC compression.

 

[Cochip]

Thanks for the heads up on finding TDC. I did a bit of both the cygnus suggestions and Cyfi6's suggestions. I believe I got it at TDC although I can't see the nose of the cam exactly, but I started with it facing the oil filler, rolled the engine back 120 degrees or so and then rolled it back forward until the notch lined up with O on the timing cover. I can just see the nose of the cam at this point, but the rotor was pointed at #1 and everything else looked right so I think I got it where it needs to be. So here's the rub I go to pull out the dizzy and it comes out pretty easily, well half of it does!!! The damn thing broke right at the cuff/pin location and I had to use a pair of needle nose pliers to remove the other half. The good news is it doesn't seem to have caused any other damage and it definetly confirms that this was were the oil leak was coming from. It also explains why my idle has been so damn weird and is the cause of the "rattling" that I was hearing. I just knew something wasn't right!!!!
So does anyone know why something like this would happen? Is this a commen issue with the 7M? Also will any dizzy from any 7MGE engine work as a replacement? There are several 80's Celicas in two of the local pick-a-parts where I have some credit to spend. I cannot afford to spend money on a remaned unit.

Thanks in advance

 

[Cochip]

Here's a picture of the carnage!!

 

[bioskyline]

only the supra and the 87+ cressida came with a 7m. the older celica-supras are a 5m, and sit on the other side of the motor

 

[Cochip]

Alright so here's an update for anyone interested. I went out the two of the local pick-a-parts and at the second one I was lucky enough to find an '88 Supra that was suprisingly intact! Someone had pulled the head, but thankfully had left the dizzy! I was really happy to have found one seeing as they online wanted $35 and not $188 which I don't have. I got it home, cleaned it up and swapped cap, rotor and the new o-ring I had originally bought to replace. The re-install went good, rotor aimed at #1, put a bit of oil on the o-ring and then gently slid it in place. I have to say it felt like a nice tight fit, actually had be a bit nervous because of how tight a fit it was, but I think I got in in there without any damage to the o-ring. Started right up, idle was already better and the timing went great. Here's the rub....after my first drive I find an oil drip! Take her around the block and stop and look......to find a consistent oil leak, worse then before. Now it's late and I have no time to dig any deeper to find the issue. Logic would say that I either jacked up the o-ring on re-installation of the dizzy or that the internal seal on the dizzy is shot! My thoughts are that since the leak is much worse then before that it must be the internal seal, but I can't do anything until tomorrow afternoon to troubleshoot it more. Any thoughts? I double checked the part number for the o-ring I got from a local Toyota Sealership and it looks right to me. Although I will say that it did not appear to fill in the grove in the dizzy as much as the old one did. It did however go in snug, so that seemed right to me. I'm getting discouraged, I just want my truck back and not leaking!!

 

[CyFi6]

Pull the cap off, it should be dry in there. If there is oil in there it is leaking internally

 

[Cochip]

Yeah that's the first thing I'm going to do and I'm hoping that's not the issue! There aren't a lot of 7mge's out there to pick parts off of and I really cannot afford to buy a remaned unit!!

 

[Cochip]

So I got home today and immediately got to checking where there is and isn't oil. No oil was found inside the cap, that's good....doesn't appear to be any new oil directly under the distributor. After a look of looking at funny angles it appears that the oil is coming from high on the block near the head. Now I can't exactly see if there is any radiator fluid with the oil, but I was curious if it is possible that the lead was coming from the head all along? What do you all think? Is there any chance that the head could begin leaking at the block? I haven't messed with the head at all and as far as I recall the head was re-torqued to correct the factory under-torque issue. I don't believe the oil has any rad fluid in it, but I'm not sure. I'm going to pull the dizzy just to check the o-ring and that'll also give me a better look at the top of the block. Any information sooner then later would be appreciated as I really need to find this issue sooner then later. Thanks so much in advance.

PS: This is a fairly significant leak, active dripping after a short drive.

 

[CyFi6]

Its possible its leaking from the head gasket. Could also be leaking from the lower rear timing cover. Make sure it is not leaking from any of the block galley plugs or camshaft/valve cover seals. Obviously I can't see it so there's not much I can do to help, but those are all the areas in that vicinity i can think of off to top of my head that you need to check. You will probably need a mirror to look up under the exhaust manifold to see where the head meets the block.

 

[Cochip]

Okay so here is an update. I double checked the distributor and the o-ring which looked okay. I re-installed it with a gasket I made from some gasket paper for a bit insurance just in case the o-ring wasn't doing the job well. Cleaned up the mess as best I could and then fired her up and took her for a spin. Initially I thought I had fixed the issue, but sure enough a drip begins!!! So I looked around really hard and it appears that there is oil coming from the weep hole at the bottom of the timing cover and I can see a leak down the front of the timing cover on the passenger side which seems to be coming from way up high on the cover. The passenger side valve cover looks good and no new oil under the dizzy. Also I could swear that I saw some antifreeze mixed in with some of the fresh oil that leaked. So could this be a leak at the head? Would I see some antifreeze and oil? Would the leak there cause leaking on the exhaust side of the block and inside the timing cover?

 

[CyFi6]

Time to pull the upper black plastic timing cover. There are 4 different annular seals in there; the 2 cam seals, one oil pump shaft seal, and the front crankshaft main seal. It sounds like your cam seals could be leaking, you will see it plain as day when you pull the timing belt cover off. If that is the case and the timing belt has oil on it, the belt needs to be replaced. With this cover off you will also get a better look at the seal between the head and the block, which is possibly leaking but not that likely. Don't jump to conclusions on the head gasket. When you open your oil cap and it looks like a chocolate milkshake in there, then you can start worrying .

 

[jenny89]

have you checked exhaust manifold gaskets and valve seals? if it seems to be that high on the block it could b coming from underneath the exhaust manifold