Thread: Finally bought a broken rxp !!!
08-25-2013, 06:05 PM #1
Finally bought a broken rxp !!!
So I finally got my hands on a broken 05 RXP with 49 hours! ( I'm completely new to 4-Tecs by the way)
I've been looking for a project like this to learn the 4 Stroke ways.....(couple 2-stroke re-builds under my belt)
This RXP has 0 compression on the #1 piston (pto) and about 130 on #2 &# 3 .....Where do I start????
What are the most common causes of this issue ? Valves will get replaced since I will be already at the top end.
Just trying to get a head start with some advice from other members.....Thanks Guys!
08-25-2013, 06:20 PM #2
Well first. Is there damage to the cases or just a dropped valve with piston/ head damage? Need to yank the engine and see what's the damage and caused it. The 4 stroke isn't as forgiving as 2 strokes and would recommend having someone local if possible to double check things or post plenty of pics and get the help that way.
08-25-2013, 06:36 PM #3
- Join Date
- Dec 2006
- Crest Hill, IL
Sounds like it lost a valve....thats common for 04/05 heads...
08-25-2013, 06:36 PM #4
08-25-2013, 06:39 PM #5
08-25-2013, 07:09 PM #6
no, if the motor is only 8.4:1 then 8.4 x 14.7 =123.5 psi and 8.5 x 14.7 = 125 and 9x 14.7 = 132.3
if you dropped a valve you might as well look for an other motor, bet ya its junk
08-25-2013, 08:20 PM #7
08-25-2013, 08:23 PM #8
now those numbers are not corrected for valve timings or oversize pistons
08-25-2013, 08:38 PM #9
- Join Date
- Aug 2013
Dropped exhaust valve?.... 72 prefix part # on the valve stem is BAD NEWS.. A Busted Intercooler core? (freeze)..... A Bent Rod that squared the piston bore..? (Engine that ingested water)? are all things to check & most pertain to the #1 cylinder failures..... Just depends on how much it got ran after the orginal damage will determine the cost to fix it.....
08-25-2013, 08:44 PM #10
Great, thanks!!!! I'm just going to start to pull it apart and see what I have..... A lot of info, but its leading me in the right direction!!!!, you suggest to pull the motor completely out or just the head?
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