Xj650h Intake manifold replacement

Hello fellow XJ'rs,

I have a used set of intake manifold's on the way and am going to replace the old ones that have electrical tape on them to hold them together. I was just looking for some added help from you guys. I have been reading up on this job and it doesn't seem too bad. Push the hoses in on the backside of the carb and loosen the clamps and the carb should just slide off then I can get to the intake manifolds. Just looking for any suggestions from the ppl on here. Any help is appreciated, this will be my first time taking the bike apart in any way. Thanks.

 

Unbolting teh airbox will allow it to slide back enough to allow for more room to get the carbs off of the engine-side boots. Pushing the airbox side boots into the airbox is also helpful. Warming the old boots with a hairdryer improves their flexability, amking the job much easier.

Here is the very important part.
The bolts securing the intake boots to the engine are soft. They will probably be corroded to some degree. Snapping one off will greatly complicate the job. While you are waiting on the replacement boots, soak the bolts with a good penetrating oil (WD-40 is NOT a penetrating oil).

Another bit of importance:
Carefully inspect the replacements for cracks. If you find any give the boots a good degrasing, a good scuffing with rough sandpaper, and coat them with an oil-resistant black RTV.

One more thing:
You can buy brand new intake boots. The cost for them has come down considerably from the days where you had to hunt and beg for an NOS set.

 

Besides the RTV that The Dude suggests; you could take it a step further and do the Inner Tube Trick.

 

Yep. That is the best way, and will be easier to do with the boots off of the bike.

 

Thanks for the input, I will definitely use some penetrating oil on the bolts before I take them off.

Hopefully the replacement boots are in good-enough condition that I won't have to repair any cracks, but I love the inner tube trick. If I would've found that on here sooner I might have tried that first with the old boots.

I just bought the bike (my first) and am mainly trying to get rid of a high idle in the engine when it warms up, the boots now are covered in electrical tape and I am hoping are the only thing contributing to the problem. I am a college student and money is a little tight (hence not going with new boots) but hopefully will be able to "spiff" the bike up in the next couple years and get her running amazing. I've been scouring through this forum and I already want to get stainless lines for/go through the brake system. Might be a winter project for me this year. Really glad I found this site, seems like you have a lot of people who know what they're talking about and am looking foreword to getting to know my XJ.

Again thank you for the input and if anyone else has any tips/advice to give I will be more than happy to read it.

 

Tip: don't die. Quit riding the bike until you've at least popped the rear wheel and physically examined, with your own two eyes, the rear brake shoes for this: http://xjbikes.com/Forums/viewtopic/t=15874.html

Rebuild the front brakes ASAP and don't run at highway speeds or in heavy traffic until you do.

Tip: don't blow it up. At the very least, CHECK the valve clearances just to be sure you aren't about to wreck the motor. Checking costs nothing but time.

Your high idle is due to an out of sync condition, improper float levels and/or a vacuum leak. If you truly want to be able to rely on the bike for transportation, then you need to fix it before you hurt it.

Carefully monitor your oil level for a sudden rise, and regularly do the "sniff test" on the contents of your sump. If the oil level rises or you smell a strong odor of gas in the oil, quit running it or you WILL blow it up.

You can't just start riding a 30-year old bike without doing some work up front; it will just make it harder (and ultimately more expensive) to accomplish in the long run.

 

before you start taking the old boots off make damm sure their bad. put your finger in there and feel around for cracks. if you snap one of those bolts off your in a world of hurt

 

OK... so I did something after reading this... I bought new boots and then started taking off the old ones.. snapped 5 of 8 boot bolts!!! I have a local cnc machinist in town.. thinking of bringing him either the whole engine to work from or just the head?? any thoughts? I don't want to go further than I should. Tried backing out the snapped ones.. 33 years of sitting in there, they aren't moving.

 

Ask the machinist. How he tackles the job will depend on what machinery he has to do the work with. For example, building a fixture to hold an entire engine in milling machine takes a lot more work than fixing just the head to the mill table. There are other ways to do the job, but you won't know if he is set up for that until you ask. Take some pictures along to help him bid the job correctly.