xstang77 2 #1 Posted October 24, 2021 (edited) Hey guys reached the point where I could use the experts. Have an 88 520h I'm getting back together from a pile of parts,I've swapped in a later early 90s p220 and I cant seem to get it to start,have fuel,and spark but no go,had to convert the harness over to the pre relay wiring so hopefully I got that right which I'm thinking I must since it turns over and sparks. Any help would be greatly appreciated thanks. Also doing a quick compression test I'm getting atleast 95 psi and around 50 on the rear which I know is bit low which could partially be my tester, but I'd imagine this should still run,I have video of this engine running just before the guy I got it from pulled it. Edited October 24, 2021 by xstang77 Share this post Link to post Share on other sites
lynnmor 6,775 #3 Posted October 24, 2021 If you have fuel and spark it will run with enough compression. That 50 psi is more than a bit low, it needs to be addressed before putting the engine in service. I do agree that it should start even with those low compression figures, my thought is that there is a problem with the carburetor. Try pouring a teaspoon of gas down the carburetor throat and immediately try to start. If you can't get a brief firing, then revisit your procedure on checking the spark. 1 Share this post Link to post Share on other sites
xstang77 2 #4 Posted October 30, 2021 Got it somewhat running seemed to be weak spark,dealing with no charge issue now and I agree lynmore, I think I'm going to pull this engine back out and steal back the original engine I put in a 416-8...im thinking the 520s a more usable and valuable tractor vs the 416-8 anyway 🤔 Share this post Link to post Share on other sites
