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Is my engine screwed

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Took my drz 400E out last weekend, and while I was riding it a rock kicked up and put a hole in my right crank case cover. As I was riding the oil all drained and the engine overheated and died on me. It didn't make any metal on metal sound it just died. It was also very hot. The coolant in the radiator was bubbling. The engine still turns over, but I am worried I either scorched a cylinder or spun a bearing. I think the first thing I should do is a compression test but I am not sure. Any input is welcomed!

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You did not "spin" a bearing. No plain bearing inserts to spin. Other damage is certainly possible. Remove the cams and inspect the journal bearings (plain but no inserts). Do a cylinder leak down test. Motor locked at TDC compression. If OK, put oil in it , start it and ride it and evaluate how it sounds and runs.

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You did not "spin" a bearing. No plain bearing inserts to spin. Other damage is certainly possible. Remove the cams and inspect the journal bearings (plain but no inserts). Do a cylinder leak down test. Motor locked at TDC compression. If OK, put oil in it , start it and ride it and evaluate how it sounds and runs.

I would fix the hole in the crank case cover first, before putting any oil in and riding it anywhere :busted:

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I think we are talking and outer case cover and not an engine case. And actually I would do an evaluation before I spent any money to fix anything. May make a bit of a mess but maybe a temporary fix with some duct tape would be good enough for a short test. There will be 2 quarts of oil to play with. Then you would know if you are just replacing an outer cover or totally rebuilding a motor.

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I would fab a case out of JB weld, scrap aluminum, aluminum foil, banana peels, whatever. Just make sure it (the case with a hole in it) doesnt leak too bad, your going to have to replace it anyways. Then fill it up with oil and run it at idle for about 2 -4 minutes to get it to temp and then shut it down and drain the oil to remove any shavings/debris if there are any. After that fill it back up and take it for a spin, at this point the damage is done and by removing any foreign debris (as you did in the previous step) you should not create any further damage. If the engine feels good then chalk it up to luck and run it. If it feels different i.e. slower or noisier, then you can start pursuing a rebuild but i personally would still run it until the performance sucks so bad that a rebuild is inevitable. But then again I'm a cheapo......

Keep in mind that whatever damage was caused is irreversible. If you can finish out the wee remaining days before snow than I would go for it, then theres the winter project........

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You did not "spin" a bearing. No plain bearing inserts to spin. Other damage is certainly possible. Remove the cams and inspect the journal bearings (plain but no inserts). Do a cylinder leak down test. Motor locked at TDC compression. If OK, put oil in it , start it and ride it and evaluate how it sounds and runs.

Did motor actually lock up or just cut out?

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i locked up my intake cam on my YFZ450 once, and the engine spun without too much resistance, but the cam journal looked like this. the rear journal is marred beyond recognition it just doesnt show too much in the picture.

IMG_2472_2.jpg

sooo, i would probably open her up and have a look.

stumbling through my photobucket, i found this picture which might inspire you to open up that engine and throw some aftermarket goodies in there, so heres some engine porn for you.

IMG_2578.jpg

IMG_2339.jpg

IMG_2166.jpg

i went into that project with absolutely no prior experience inside an engine, and even hough i blew it up more than once, it was one of the most educational experiences ive ever had, and im glad i did it myself. you can do it too!!! :busted:

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Hey thank you everybody for your input I will download a pic of the "broken case cover." it is the one on the right side of the engine in front of the clutch cover. If it where the case I would really be screwed so I am thankful for that.

I enjoy all of your advice and I will definitely take heed to all of it. I already started taking the plastics off so I can pull the valve cover off there. I am happy to hear that the crank bearings are regular ball bearings and not journal bearings. That gives me some hope!

The engine did not seize up on me it just got extremely hot and died, which is just as bad I am sure.

I plan on taking the valve cover off and examining the cam shafts and journals. I couldn't view your pics Joester because my work blocked them, but I will look when I get home. Thank you! While I have the valve cover off i am going to do a cylinder leak down test and that will be my first real indicator. After that I will seal up the hole put oil in her and do exactly what Jwayne said, "which I appreciate very much. I would have probably done more damage." After that I will evaluate what needs to be done from there.

Unfortunately I live in southern California where we don't really have much of a winter and the riding season actually just begun for the most part so I shot myself before the battle began!

Thank you everybody for the advice and I will keep u updated with pics and I am sure tons more questions!

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I tore it down this weekend and it is as bad as I figured it would be. The exhaust cam shaft had deep groves cut into it, which also ate up the cam journals in the head, so it's completely screwed. Also I took the cylinder and piston off and there were four wear marks on the piston, and cylinder that where pretty bad to. I think that from here it is time to invest in a big bore kit. Any recommendations?

I am looking at the wiseco set up, but the athena looks pretty good to.

Also does anybody know a good way to test crankshaft bearings while I have the top end off of it?

I wanted to post pics but I am pretty computer illiterate, so I can't figure out how to on here I clicked the tab up top but it didn't work for me. If someone tells me how I will try again!

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Jump for the CW BB kit. Find another head on fleabay. I don't know any means to save the journals.

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The cylinder works big bore is the best value...

If it was my bike I would replace the crank bearings...

Upload your pics to photobucket then copy from photobucket album to TT.....http://www.steves-digicams.com/knowledge-center/how-tos/online-sharing-social-networking/how-to-upload-photos-to-photobucket.html

Edited by CraigoDRZ400sm

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Jump for the CW BB kit. Find another head on fleabay. I don't know any means to save the journals.

There are several companies that can fix cam journal damage, but IMHO it is not worth the cost unless the head has other work done to it your trying to save. (a correctly working porting job, otherwise undamaged big valves, ect)

But with so many good used standard heads available.. spending money to have an otherwise stand head fix is not economical.

Engine dynamics can fix you up if you want to go repair route.

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I tore it down this weekend and it is as bad as I figured it would be. The exhaust cam shaft had deep groves cut into it, which also ate up the cam journals in the head, so it's completely screwed. Also I took the cylinder and piston off and there were four wear marks on the piston, and cylinder that where pretty bad to. I think that from here it is time to invest in a big bore kit. Any recommendations?

I am looking at the wiseco set up, but the athena looks pretty good to.

Also does anybody know a good way to test crankshaft bearings while I have the top end off of it?

I wanted to post pics but I am pretty computer illiterate, so I can't figure out how to on here I clicked the tab up top but it didn't work for me. If someone tells me how I will try again!

You can use a dial indicator to measure movement of the crank ends.. coupled with how they “Feel” when you rotate the crank (free to rotate, no catches or rough feeling) You can look at the crank bearings somewhat with the side cover off.. See if there is an pitting, flaking, or other visible damage.

If you’re looking to replace the top end, have a look at Cylinder Works for a 94mm big bore kit.. Quality product, complete package at a great price.

For posting pics, you need to be a TT Team member to upload directly to the TT Server, or you can host them on any of the free services like photobucket.com and then link to them here using BB code or the insertimage.gif button widget found in the reply view.

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There are several companies that can fix cam journal damage, but IMHO it is not worth the cost unless the head has other work done to it your trying to save. (a correctly working porting job, otherwise undamaged big valves, ect)

Engine dynamics can fix you up if you want to go repair route.

i went through engine dynamics when i screwed my head up, and they did an awesome job. mike there is a great guy, and i would recommend them, but sadly, this is only logical like you said if you are trying to save the head because it is of larger value than the repair work (like mine was which had a $455 port job)

but if you do want to get the head fixed, i highly recommend engine dynamics.

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