New Seca 750 owner w/ pics

New owner and new to site. 81 750xj750 Seca, paid $550 w/ title

The good: fires right up with a little choke. Idles. Runs. Drives. Seat is like new. No dents in tank and very very little rust all around bike. Rear brake works. Computer is in good shape, dash works perfectly.

The bad: cracked windscreen, am painting.. Everything is dry rotted, nothing leaks majorly. The tank cap is a total pain to open, already twisted a key in it. Starter selenoid is jumped with a pushbutton under side cover. One sider cover is velcrode on.

The ugly: Front brakes nonfunctional. Tires dry rotted completely -need replacing. Valves lifters have never been reshimmed. Final gear is smooth but has not been recently serviced.

Dropped the bike going 5mph or less my first day.. was able to gently set it down. Oil and gas coming out of airbox drain tube.. Fired her right up to be sure nothing major broke.. Is low on oil and the air filter is junk now.

Waiting on parts to make some repairs.

Thanks for reading.

 

Welcome Rex, you seem to have a good handle on things, I would tell you that the final drive is bullet proof as long as it has never been without oil. I did notice in one of your pics, that the vacuum hose to your petcock appears to be incorrectly routed. It should be attached to one of the carb boots next to the head. But I don't know, it might work just as well there. Now that I look closer, it appears that what I thought was the vacuum hose is actually the fuel hose.

 

Today I am going to clean and dry the old air filter the best I can then I will reinstall and add a little motor oil and warm the bike up a few minutes. I want to keep the new battery fresh and not let any gas sit in the carb for too long. I figure after tipping it and having oil and gas spill out of airbox I should run the bike a few more times to be sure the mixture isnt fowling up my carbs. Have to say though, with the oil/gas mix in the airbox before cleaning the motor started right up and didnt seem to mind having oil make its way up to the intake.

Any reason why this is a bad idea? I want to keep her running every couple days while I make other non engine repairs. I know I shouldnt use the old nasty air filter but its better then no filter and I dont want to wait a week for my new one in mail before starting the bike again

Comments?

 

Thanks for your reply. I never noticed that before.. I guess because the motor and petcock work well together and I have had no issue there. Is that hose going into the airbox boot supposed to plug into the carb boot instead?

 

The air filter should be alright, if you can blow compressed air from the inside out that would help. Wouldn't worry about the oil in the air box you should have a drain on the bottom of it.

 

So you do have a hose going to that boot?! The correct place for the vacuum hose is at one of the carb to head boots.

 

OOooh yeah she drained oil/gas for 2 days straight from that tube. I detailed the airbox with papertowel and qtips for an hour. She is all set and clean. Appreciate the info!

Waiting on oil filter cap o ring before changing oil.. I will check but doubt the old oring is viable for reuse.

I need a small oring for that oil filter cap bolt too I believe.

 

I bet the original owner made some adjustments or his mechanic did anyway. I will inspect and take more detailed photos of the routing then compare to my dealership service manual.

But hey, if it aint broke dont fix it!

 

Twenty-three thousand miles and the valves have never been done? Do this ASAP! Then new tires and fix the brakes. All this before you ride. I'm sure you'll get a lot more tips. There's a lot that needs to be done to this bike but it's worth the time and effort.

And welcome to the site!

 

Honestly I guess the valves Could have been reshimmed by the original owner because I never asked but I was not told either.

Is it true that a mechanic can listen with a scope to diagnose tight clearance? I keep getting told not to open the top end if there is no symptoms or noise. Does run and starts great. Ideas?

I better get them checked anyway.. huh?

 

Here's the problem with " if it ain't broke don't fix it" if you leave it as it is, you may encounter fuel starvation when idling for prolonged periods of time, because there may not be enough vacuum to keep your petcock open. Whereas if you route it as the engineers intended, you'll always have adequate vacuum.

 

I will compare to the service manual routing before taking it on the road. Appreciate the concern thank you.

 

Rex, the only good way to check valve clearance is to take measurements with feeler gauges. You have a "diamond in the rough" here, if you go cheap now you'll pay for it later. It's not a hard job to check your clearances, and if you deal with this as we advise, your engine will be very happy. Also check for rear brakes for "shoe de-lamination", though rare it happens enough to warrant this warning.

 

Hi Rex. You can't tell enough about the valves by listening, they will need to be checked. They actually become quieter when tight, and it runs seemingly fine until a valve burns. The correct valve clearance is necessary for heat transfer, proper compression, carb sync/adjustment, etc. It is the first step in proper tuning and cannot be skipped. There are some great how-to's on this site. Use the search function and do a lot of reading.

 

Iiiiiiiiiii know I DO need to have it checked. I am debating doing it myself or having a local reputable mechanic do it, has nothing to do with money, I just do not trust myself to get it right. The guide on here is nice and I have a guide in my manual too.

 

Rex, post your bike info and location in your sig, it may be that there is someone here who is close by you! You have to make sure the local mechanic knows how to work on these bikes. Most Don't! The bikes are too old and they simply aren't familiar with the specifics. Many stories on here of people paying $$ to have work done and still not done right. Then they come here, learn how, try themselves, and get it right if they are willing to follow advice. There are real experts here that have helped me and everyone else who asks!

 

I have tons to learn from you alone I need my master cyl and front calipers rebuilt! Seems cheaper to buy used and working then swap if i can find a front end or donor.

Top end work is in my scope and the parts are actually not overpriced. Will need the metric feeler and gasket maker. And yics tool. Might as well try to clean it up while top is off.

 

Anyone in Metro Denver or close enough willing to walk me through my first reshimming? Will pay cash for your time to work with me on it. Hoping you will have the Yics tool and some spare shims possibly! And feeler...

Pm me or reply.

Everyone else, very much appreciate the words. Will keep posting pics as I progress. Going to plan on painting my worn windscreen and maybe find replacement hardware with rubber bushings.

 

Here is an excellent walk through on the valve shim check/replace:

http://www.xjbikes.com/Forums/viewtopic/t=14827.html

bigfitz's knowledge knows no bounds!

Please be sure to check this ASAP. Would hate for you to do some damage to the top end. :cry:

And the brakes a actually a higher priority.

Good luck and be sure to ask for guidance on the boards. There's a treasure trove of information available here.

 

Painting windscreen black

Taped off

Painted
will post later when assembled. Found out one headlightt mount was all the way loose. Tightened that...

Got sparkplug stuff..

Here are the old plugs. Good shape except one coated in oil from my lay down. Still sparked though.

I thought it super odd that i had to unscrew the topand connector off the sparkplugstuff for it to fit my cables.. anyways.. they work.

 

Cold and rainy day today.. along with new plugs I flushed motor oil with a gallon then drained to proper level 3/4 up window. Will do oil filter and new motor oil when o ring arrives.

I blew out and dried out old air filter just for todays warm up.. installed that into clean airbox.

Took Forever to start. Used no starter fluid or anything. Kept petcock on always. Kept cranking all through my battery until finally she booted up at 3/4 choke. Idled. Idled lower @ 1050 ish with choke half open. Ran it for 5 mins then rolled throttle and revved to 3k a few times. Let it idle more then turned her off after about 10 mins.

Happy with results. Glad I didnt drain my bike battery getting her started.

I should start it once daily to keep her fresh huh? While I do non motor repairs..

 

Custom hardware

Dash view

Side view and front

 

Rex, it appears that your petcock plumbing is correct after all.

 

Thanks. I was looking for someone to confirm.

It looks as if my master cylinder is intact and may even be in decent shape, but I am missing the fluid resevoir that attaches to the handlbars. Can i use Any motorcycle brake fluid resevoir for a bench test and possibly fulltime use?

 

Hey rex,

Just to reiterate, valve adjustments is a regular maintenance thing. You only have to remove the tank, left engine cover, and valve cover...it may seem like you're opening the engine up, but you're really just peaking under the hood.

It is not a "top end job." If your motor blows good compression, then you don't need to rebuild it, top or bottom end. But the valves NEED to be in spec, or a rebuild will be in your immediate future.

Don't bother taking it to a shop, just take your time, and ask questions, you seem like the kind of person who can get this right with the right info.

On the brake master cylinder, are you talking about the stock MC/resevoir? Because on the 750 secas, the resevoir is behind the headlight, and you can see it in your first post, second picture. It's the odd looking black extruded prisim with a plastic allen bolt. Remove that bolt to fill.

Rebuild your brakes, caliper, MC, new lines, and get new shoes for the rear. These can perform fine under "normal" conditions, then fail when you need them most in a panic stop. I know it will seem expensive (and the 750 seca will have 4 brake lines to replace, in addition to a cable) but being able to stop is more important than being able to go.

Or you could get a handlebar mounted MC from a different bike, and install. Regardless, the seals in the MC and calipers from ANY motorcycle are designed with 4 and 2 years of life expectancy.

 

OooOooh I understand. So that Is the resevoir and master cylinder alll in one? And I can fill That and flush and bleed and see if my brakes unfreeze?

If that doesnt work I get a MC from any other bike as long as it had dual single piston calipers so the hydrolic pressure will be strong enough? Or any other bikes MC will hookup to that front distributor that sends the lines down to each caliper?

I am going to order the YICS tool once my first order with chacal goes through smoothly.

Can anyone tell me if I need to start the bike and idle it a few times a week to keep fresh fluids flowing until I get it rolling? Wont be checking valvespecs for a month and I know it shouldnt sit. I think I have learned I need to never move the petcock from on regardless.

 

Kindof, the resevoir does come off, but you have to be very careful, because the grommet between the two is not available. Search the site for "handlebar mounted master cylinder" it's a common mod for 750 secas.

Letting it sit isn't going to change your situation, in fact, it'll be better to not run it until you get the valves/carbs sorted out. The only thing that can happen when you let these bikes sit is gumming up are the carbs. You say it runs and drives, but how much running and driving was the PO doing before he sold it? If the answer is not much, you'll likely need to dive into the carbs to get it running RIGHT. It may run and idle, but getting it running RIGHT is where you'll want to end up. And carbs are one of those things that it's better to spend the time and money getting it right the first time, rather than trying to troubleshoot symptoms with interrelated causes.

Also, if you were leaking oil out of the airbox, it means your carb float needles weren't holding back the gasoline, and filled your crankcase with gas. Unless the PO just overfilled it, but the former is more likely, and you'll have to clean/rebuild the bottom end of the carbs to fix it. And if you left your petcock on ON and not PRI, then it likely needs a rebuild to.

After all that is done, you'll change the oil and filter, because gas diluted oil will ruin the engine if it's run like that (not that you've done any damage yet, but take it out on the road, and you'll wreck the engine).

 

Okay here is what I did today.. and the gas/oil mix is just a guess, could be purely oil.. But came out drain tube for airbox when I dropped the bike..

Anyway, what is this with the petcock? People on this site say to literally never change it from On unless I just ran out of gas which never happened.

I flushed the oil with a gallon of 20w50 and refilled. Added 87 octane gas.

It is 70the degrees out today, bike fired up first try and idled at 1500 with 3/4 choke then idled at 1050 with 1/4 choke. Turned her off after idling 10mins and making sure she responded well to throttle.

Again, what is wrong with the Petcock being On always? Works great..

And by flushing the motor with an extra gallon of oil, I fixed any potential gas/oil mixup right?

Thank you for your comments and help, please work with me on this I am totally new to the xj platform... other bike was gs500 twin cylinder.

 

And isnt anyone going to tell me 'good job' on my painted windscreen? Replaced those stupid plastic bolts and nuts and used steel. Now the windscreen is less likely to come off at 50mph and take out my front teeth! And the paint hides the cracks and missing pieces!

Someone comment!

 

Well if you sniff the "oil" can can smell gasoline, then there's gas in it.

The petcock is vacuum operated. You'll notice two hoses on it, one that goes to your carbs, and one that goes to an intake joint, usually #3. It has 3 positions, ON, REServe, and PRIme. Notice there is no OFF.

ON and RES take gas from different positions in the tank, ON is higher than RES. The petcock has a diaphragm valve that is actuated by the vacuum in the intake. The PRI position bypasses this valve. You only need PRI if your float bowls are empty, either from sitting (gas evaporates) or running out of gas.

When the bowls are empty, no fuel will get to the engine. So if you are trying to start the engine, gas will only flow to the carbs when #3 produces a vacuum, and you'll never start. That's why there's a PRI setting.

I guess oil could end up in the airbox from a tip over. Checking your float and petcock is easy though. Simply disconnect the fuel line with the petcock on ON, get a catch pan, and see if fuel leaks out on ON or RES. Then confirm fuel flow on PRI. For the carbs, check the float height using the clear tube method. If both of these tests pass, then you're fine.

 

Nice job on the windscreen.

 

Thank you and thank you. Busy filling old empty liquor bottles with used motor oil out of my oil pan...

 

My front brakes 'were' broken. Took off the fairing to investigate...

Plastic allen screw is stripped. Used needle nose to unscrew. Tons of fluid, overfilled a little. Used a socked, pressed brake lever and unscrewed bleeder on right side caliper. I bled air burps then fluid. Bled left caliper. Fluid came out. Repeat and Repeat...

I now have front brakes! Turns out the pads are practically new. Almost no wear.

Changing my sig...

 

I'm not a fan of the painted windscreen, simply because of the fact you can't, you know, see through it.

Safety issue in my mind.

 

You must be short.

 

I am 5'9'' and I tower over the windscreen.

Moot point anyway, I only painted the 30 yr old windscreen because it was no longer clear. I was unable to see through it due to scratches, smudges, fading, etc. The black paint is just a stealthy cover up.....

 

And to add, I replaced the stupid PLASTIC head bolts and PLASTIC nuts with Steel and rubber washers. Not to mention white plastic bolt heads are ugly on black fairing.

 

Unless someone removed them, you also have anti-dive units in the front brakes that also require bleeding. The bleed screw is a high point relative to the line that goes in, so it can trap air too. And also, change your brake fluid if you haven't already. No sense running with the old fluid.

My allen head is kinda stripped too, but once it's broken loose, I can generally open and close it carefully using the allen key. If it's really stuck, then you just whip out the pliers.

I think the proper solution to an old windscreen is a new one . Also, I would be concerned about the metal making contact with the windscreen,(in between the grommets). The whole dissimmilar material interface might cause problems down the road, so keep an eye out for cracks.

Finally, brake pads might have a lot of thickness, but it they are old enough they can crumble. If you aren't sure of their age, it's a small price to pay for peice of mind.

 

Good call

 

Rex - I made a cardboard template of my windscreen and then went to the hardware store and bought some lexan and made my own windscreen (twice actually). I just heat it up slowly and evenly with a heat gun and then I slowly form it to shape.

For the screws I ordered black plastic screws from McMaster Carr. I suppose having used rubber washers as insulators you will probably be ok but I really don't know.

You're doing great so far. Keep up the good work and ride safe.

 

Rex,
Love the bike (windscreen too), best of luck. This spring I installed SS brake lines from Chacal after thorough brake system overhaul, calipers, M/C and the difference is impressive. Highly recommend it..

 

I love the positive feedback thanks guys. I got insurance yesterday $185/yr with Progressive. Ready for plates and new tires. I will search for forum for recomendations and I wonder if I can go larger than 120 in rear.

 

Got new air filter. I should start her up later and see how she likes it...

 

I need some advice from you guys.

I want to flush and refill the final drive so I got the correct hypoid oil 8090.. The refill cap looks dirty but looks like it will unscrew.

The drain is rusted and I dont want to try anything until I come here first. I didnt even put a socket on it yet.I have BP Blaster, sand paper, maybe WD40, and hand powered socket set.. How should I proceed? Do I need a mechanic with a torch?

 

Rex, don't worry about the final drive drain plug, just put a socket with a breaker bar on it and slowly pull until the seal breaks. I not very likely to be rusted.

 

so you are saying even though the bolt and surroundings are covered in rust.. its not likely to overtorque and snap off because it is heavy duty? so i should just go for it?

 

Hit that drain plug with some Kroil first and let it sit overnight.

 

That's right, trust me, you cannot mess up that drain plug unless you mistakenly tighten it,(and I mean you really have to put major torque on it) If you put the breaker bar and socket on with the breaker bar facing to the rear, and pull toward yourself, I GAR-AN-TEE it will come loose.