Is the LS an interference engine?
12-04-2007, 09:47 AM
#1
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Is the LS an interference engine?
I tried to look it up, alot of people said all honda motors are interference engines. But i saw a couple people say that the USDM ls is a non interference..
12-04-2007, 09:54 AM
#3
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Re: Is the LS an interference engine? (ek forever guy)
Yes it is.
Meaning that it's possible for valves to make contact with the pistons and do serious damage in the event of a broken timing belt.
...but I have personally seen a half dozen B18A/B engines with broken timing belts run fine after the timing belt broke and we replaced it with a new one.
Whether or not you bend valves depends on thr rpm at which the engine was when the belt broke, and if the tranny is a 5-speed or auto - autos tend to be less liklely to bend valves because 5 speeds MAKE the engine coast down if in gear and usually that destroys the valvetrain.
Meaning that it's possible for valves to make contact with the pistons and do serious damage in the event of a broken timing belt.
...but I have personally seen a half dozen B18A/B engines with broken timing belts run fine after the timing belt broke and we replaced it with a new one.
Whether or not you bend valves depends on thr rpm at which the engine was when the belt broke, and if the tranny is a 5-speed or auto - autos tend to be less liklely to bend valves because 5 speeds MAKE the engine coast down if in gear and usually that destroys the valvetrain.
12-04-2007, 10:15 AM
#6
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Re: Is the LS an interference engine? (Chris Hanson)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Chris Hanson »</TD></TR><TR><TD CLASS="quote">All Honda motors are interference. Hence the valve reliefs in the piston tops.</TD></TR></TABLE>
No they're not.
There are 1.8L and 2.0L SOHC engines found in Preludes and Accords that are not interference design, and in fact, these engines use an external drivebelt to drive the waterpump as oppsed to the usual timing belt driven waterpumps we see on D and B series engines.
You're right in every Honda engine that we'd actually care about is interference though.
No they're not.
There are 1.8L and 2.0L SOHC engines found in Preludes and Accords that are not interference design, and in fact, these engines use an external drivebelt to drive the waterpump as oppsed to the usual timing belt driven waterpumps we see on D and B series engines.
You're right in every Honda engine that we'd actually care about is interference though.
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12-04-2007, 11:38 AM
#8
Honda-Tech Member
Re: Is the LS an interference engine? (ek forever guy)
i dont think they are. i have replaced timing belts for people that broke it and motor still ran perfectly fine. i"ve done it at least 3 times. just do a leak down and compression after you done. the leak down test will tell you if you bent a valve or not.
12-04-2007, 11:41 AM
#9
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Re: Is the LS an interference engine? (fmrprojects)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by fmrprojects »</TD></TR><TR><TD CLASS="quote">i dont think they are. i have replaced timing belts for people that broke it and motor still ran perfectly fine. i"ve done it at least 3 times. just do a leak down and compression after you done. the leak down test will tell you if you bent a valve or not. </TD></TR></TABLE>
Well I've seen one personally at my shop that did bend valves when the timing belt broke, but i have also done three or so that were just fine too.
Were the ones you did 5 speed or auto cars?
Well I've seen one personally at my shop that did bend valves when the timing belt broke, but i have also done three or so that were just fine too.
Were the ones you did 5 speed or auto cars?
12-04-2007, 11:42 AM
#10
Honda-Tech Member
Re: Is the LS an interference engine? (B18C5-EH2)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by B18C5-EH2 »</TD></TR><TR><TD CLASS="quote">
Well I've seen one personally at my shop that did bend valves when the timing belt broke, but i have also done three or so that were just fine too.
Were the ones you did 5 speed or auto cars?</TD></TR></TABLE>
5 speed. and they were just cruising. if this guy was smashing, thenthe vlves might have bent
01-16-2020, 03:54 PM
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Re: Is the LS an interference engine? (Chris Hanson)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Chris Hanson »</TD></TR><TR><TD CLASS="quote">All Honda motors are interference. Hence the valve reliefs in the piston tops.</TD></TR></TABLE>
No they're not.
There are 1.8L and 2.0L SOHC engines found in Preludes and Accords that are not interference design, and in fact, these engines use an external drivebelt to drive the waterpump as oppsed to the usual timing belt driven waterpumps we see on D and B series engines.
You're right in every Honda engine that we'd actually care about is interference though.
No they're not.
There are 1.8L and 2.0L SOHC engines found in Preludes and Accords that are not interference design, and in fact, these engines use an external drivebelt to drive the waterpump as oppsed to the usual timing belt driven waterpumps we see on D and B series engines.
You're right in every Honda engine that we'd actually care about is interference though.
01-17-2020, 04:15 AM
#12
Re: Is the LS an interference engine?
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